CN203502587U - Pulse/phase integrated laser range finder - Google Patents
Pulse/phase integrated laser range finder Download PDFInfo
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- CN203502587U CN203502587U CN201320600391.1U CN201320600391U CN203502587U CN 203502587 U CN203502587 U CN 203502587U CN 201320600391 U CN201320600391 U CN 201320600391U CN 203502587 U CN203502587 U CN 203502587U
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Abstract
The utility model belongs to the field of laser range finding technologies, and particularly relates to a pulse/phase integrated laser range finder. A narrow pulse generating circuit and a sine wave generating circuit are connected with a semiconductor laser through an analogue switch A; a branch of laser emitted by the semiconductor laser is inputted in an APD detector after passing an emitting mirror and a measured object and being received by a receiving mirror, and an echo signal is outputted after the branch of the laser is amplified by an operational amplifier B; the other branch of the laser emitted by the semiconductor laser is inputted in a PIN detector, a reference signal is outputted after the other branch of the laser is amplified by an operational amplifier A; an analogue switch B receives the echo signal and the reference signal, and the analogue switch B can be switched to be connected with an analogue switch C or be connected with the analogue switch C via a frequency mixing filter circuit; and the analogue switch C is connected with a double channel fast comparator which is connected with a time interval measuring circuit. The pulse/phase integrated laser range finder solves the problem that one laser range finder cannot have two measuring modes of pulse and phase.
Description
Technical field
The utility model belongs to laser ranging technique field, is specifically related to a kind of pulse/phase place integral type laser range finder.
Background technology
Laser range finder is a kind of use laser as surveying wave beam, measures the length measuring instrument of reflecting surface range transmission point absolute distance.The a series of advantages such as laser ranging has non-cpntact measurement, measuring accuracy is high, resolution is high, antijamming capability is strong, volume is little and lightweight, in various measurement industries, be widely used, no matter be in military field, or at aspects such as scientific experimentation, construction production, capital constructions, all play an important role.
According to laser distance measuring principle, the laser range finder that can realize noncooperative target (no-mirror, target version) range finding can be divided into two kinds of pulsed and phase types.
Pulse distancemeter principle is by measured target transponder pulse formula laser beam, and measures the laser turnaround time, and the velocity of propagation according to light in atmosphere is calculated and shown that measurement point is to the distance of target.Principle and the structure of tellurometer are simpler, and ranging is far away, and shortcoming is that Models of Absolute Distance Measurement Based precision is lower, and the blind area that has short range to measure.Conventionally impulse method operating distance is the extremely thousands of rice of tens of rice, and error, in 1m left and right, is generally used for long-distance ranging.
Phase laser distance measurement is to adopt sine wave signal to modulate laser, the range information that between the reception light of the light modulated of utilization transmitting and measured target reflection, the phase differential of light intensity comprises is realized the measurement to measured target distance, has advantages of that measuring accuracy is high, resolution is high.While adopting noncooperative target, the operating distance of phase distancemeter generally, several meters to tens meters of zero points, is generally no more than 200 meters farthest, and range error can be controlled in 2mm.
In some special application scenarios, both having needed has measuring distance far away, to find in time, detect several kilometers of outer distant objects, need to when short range (in tens meters to zero point several meters in), there is higher detection accuracy again, to carry out accurate control operation.Conventional laser range finder, all only has a kind of distance measurement mode, can not meet current measurement demand: the far away but short range of pulsed measurement range has blind area, precision low; Ranging phase method precision is high, and measurement range is little.If integrated two cover stadimeters in measuring system, carry out respectively pulsed, phase type range finding, just need to have independently laser instrument, transmitting/receiving optical system, Circuits System, not only cost doubles, and the increase of system bulk, weight, power consumption is also unacceptable.
Summary of the invention
The purpose of this utility model is to provide a kind of pulse/phase place integral type laser range finder, can not possess the problem of pulse, two kinds of measurement patterns of phase place to solve separate unit laser range finder.
For achieving the above object, technical solution adopted in the utility model is:
Pulse/phase place integral type laser range finder, comprises the double mode modulation circuit of Laser emission pulse/continuous wave and receives the double mode demodulator circuit of signal pulse laser flying time/phase differential; The double mode modulation circuit of Laser emission pulse/continuous wave comprises narrow pulse generating circuit, sine wave generating circuit, analog switch A, semiconductor laser, transmitting mirror, reception mirror, PIN detector, APD detector, operational amplifier A, operational amplifier B; Narrow pulse generating circuit, sine wave generating circuit are connected with semiconductor laser by analog switch A; Laser one tunnel of semiconductor laser transmitting is inputted APD detector through transmitting mirror, measurement target, reception mirror after receiving, and after operational amplifier B amplifies, exports echoed signal; Another road input of the laser of semiconductor laser transmitting PIN detector is exported reference signal after operational amplifier A is amplified; Receive the double mode demodulator circuit of signal pulse laser flying time/phase differential and comprise local oscillator sine wave generating circuit, analog switch B, mixing and filtering circuit, analog switch C, two-way high-speed comparator, time interval measuring circuit; Analog switch B receives reference signal and the echoed signal that the double mode modulation circuit of Laser emission pulse/continuous wave produces, and analog switch B can switch to analog switch C and be connected, and also can after mixing and filtering circuit, be connected with analog switch C; Analog switch C is connected with two-way high-speed comparator, and two-way high-speed comparator is connected with time interval measuring circuit.
Described narrow pulse generating circuit is the large current, narrow pulse generating circuit based on CPLD programming device and snowslide pipe, as the signal source of pulsed modulation.
Described sine wave generating circuit is the sine wave generating circuit based on Direct Digital Synthesis-DDS principle, and sinusoidal signal is amplified as modulated continuous wave signal source through 7 rank ellipse filtering circuits and power amplification circuit.
Described analog switch A, analog switch B, analog switch C are the analog switch of Low ESR, high-isolation.
Under narrow pulse generating circuit, two kinds of patterns of sine wave generating circuit, signal is all that the light intensity of laser is modulated, and the laser pulse of high-peak power, narrow pulsewidth is sent in drive laser work, or the sinusoidal wave laser of setpoint frequency.
Under pulse ranging pattern, while being pulse generating circuit work, by single-chip microcomputer, operate control, when selecting laser instrument driving source passage, by two-stage analog switch B, analog switch C with reference to signal, the direct gating of echoed signal to two-way high-speed comparator, by wave shaping, be the step signal that rising edge is steeper, then go out reference signal and the laser flying time interval corresponding to echoed signal by follow-up high precision time interval measurement circuit measuring, be multiplied by the light velocity and draw tested distance.
Under phase ranging pattern, while being sine wave generating circuit work, before laser works, by two-stage analog switch B, analog switch C, carry out channel selecting, with reference to signal and echoed signal, switch to mixing and filtering circuit, the output of mixing and filtering circuit is transferred to two-way high-speed comparator input end, when starting laser instrument sine wave generating circuit, start the local oscillator sine wave generating circuit with certain frequency difference, when mixing and filtering circuit receives reference signal, after echoed signal, carry out mixing and filtering with local oscillation signal respectively, the entrained phase information of high-frequency modulation signal is demodulated to low-frequency sine signal, again by the two-way high-speed comparator of rear class, it is poor that time interval measuring circuit is measured signal time, as division, obtain the poor ratio of corresponding phase with the frequency difference cycle, do multiplication with the corresponding survey chi of selected modulating frequency constant and can obtain tested distance.
The obtained beneficial effect of the utility model is:
Pulse/phase place integral type laser range finder described in the utility model solves the problem that separate unit laser range finder can not possess pulse, two kinds of measurement patterns of phase place, utilize Low ESR analog switch laser instrument to be carried out to the circuit structure of timesharing modulation, signal demodulation, realize same laser range finder and possess the advantage that pulse ranging measurement range is far away, in the time of having advantages of again closely, phase ranging precision is high, resolution is high.Use light power meter, oscillograph, spectrum analyzer to carry out Measurement and analysis to reference signal, prove that the indexs such as optical signal pulses peak power, continuous wave average power, frequency spectrum all meet design requirement, and have realized the bimodulus modulation function to same laser instrument; Under two kinds of distance measurement modes, measure respectively each node signal of two-stage analog switch input and output in demodulator circuit, signal amplitude, frequency, frequency spectrum also all meet design requirement, and have realized the double mode demodulation function of design.The test of find range of the laser distance measuring system of application design, the phase type measuring repeatability of finding range reaches 1mm, error 2mm; Pulsed range finding measuring repeatability reaches 0.1m, and error 1m, has well realized design function, and effect is good.
Accompanying drawing explanation
Fig. 1 is pulse/phase place integral type laser range finder structural drawing described in the utility model.
Embodiment
Below in conjunction with the drawings and specific embodiments, the utility model is elaborated.
As shown in Figure 1, pulse/phase place integral type laser range finder described in the utility model comprises the double mode modulation circuit of Laser emission pulse/continuous wave and receives the double mode demodulator circuit of signal pulse laser flying time/phase differential;
(1) the double mode modulation circuit working of Laser emission pulse/continuous wave principle:
The double mode modulation circuit of Laser emission pulse/continuous wave comprises narrow pulse generating circuit, sine wave generating circuit, analog switch A, semiconductor laser, transmitting mirror, reception mirror, PIN detector, APD detector, operational amplifier A, operational amplifier B; Narrow pulse generating circuit, sine wave generating circuit are connected with semiconductor laser by analog switch A; Laser one tunnel of semiconductor laser transmitting is inputted APD detector through transmitting mirror, measurement target, reception mirror after receiving, and after operational amplifier B amplifies, exports echoed signal; Another road input of the laser of semiconductor laser transmitting PIN detector is exported reference signal after operational amplifier A is amplified;
For realizing the double mode modulation of pulse/continuous wave, designed the large current, narrow pulse generating circuit based on CPLD programming device and snowslide pipe, as the signal source of pulsed modulation; Designed the sine wave generating circuit based on Direct Digital Synthesis-DDS principle, the oval filtering circuit in 7 rank and power amplification circuit, using sinusoidal signal power amplification as modulated continuous wave signal source.Use the analog switch A of Low ESR, high-isolation as switching device, required exciting signal source is connected to semiconductor laser drive end, after selected a kind of distance measurement mode, by Single-chip Controlling, wherein a kind of signal source circuit is worked.Under two kinds of patterns, signal is all that the light intensity of laser is modulated, and the laser pulse of high-peak power, narrow pulsewidth is sent in drive laser work, or the sinusoidal wave laser of setpoint frequency.
For realizing distance measurement function, Emission Lasers is separated a branch of reference light and is used PIN detector to receive by light splitting optical path, and after operational amplifier A is amplified, conduct is with reference to signal; The laser signal being reflected back from measured target receives by APD detector, and after operational amplifier B amplifies, the echoed signal of time or phase information is carried in conduct.
(2) receive the double mode demodulator circuit principle of work of signal pulse laser flying time/phase differential:
Receive the double mode demodulator circuit of signal pulse laser flying time/phase differential and comprise local oscillator sine wave generating circuit, analog switch B, mixing and filtering circuit, analog switch C, two-way high-speed comparator, time interval measuring circuit; Analog switch B receives reference signal and the echoed signal that the double mode modulation circuit of Laser emission pulse/continuous wave produces, and analog switch B can switch to analog switch C and be connected, and also can after mixing and filtering circuit, be connected with analog switch C; Analog switch C is connected with two-way high-speed comparator, and two-way high-speed comparator is connected with time interval measuring circuit;
The Low ESR high-isolation analog switch B, the analog switch C gating structure that have designed two-stage, realize the switching of demodulation modes.Under pulse ranging pattern, by single-chip microcomputer, operate control, when selecting laser instrument driving source passage, by two-stage analog switch B, analog switch C with reference to signal, the direct gating of echoed signal to two-way high-speed comparator, by wave shaping, it is the step signal of steep (ns level) of rising edge, by follow-up high precision time interval measurement circuit measuring, go out reference signal and the laser flying time interval corresponding to echoed signal again, be multiplied by the light velocity and draw tested distance (echoed signal time delay is directly proportional to the distance of measured target).
Under phase ranging pattern, before laser works, by two-stage analog switch B, analog switch C, carry out channel selecting equally, with reference to signal and echoed signal, switch to mixing and filtering circuit, the output of mixing and filtering circuit is transferred to two-way high-speed comparator input end, when starting laser instrument sine wave generating circuit, start the local oscillator sine wave generating circuit with certain frequency difference (generally at tens kHz), when measuring system receives reference signal, after echoed signal, carry out mixing and filtering with local oscillation signal respectively, the entrained phase information of high-frequency modulation signal is demodulated to low frequency (corresponding with frequency difference) sine wave signal, again by the two-way high-speed comparator of rear class, it is poor that time interval measuring circuit is measured signal time, as division, obtain the poor ratio of corresponding phase with the frequency difference cycle, doing multiplication with the corresponding survey chi of selected modulating frequency constant can obtain tested distance (surveying chi length and selected modulating frequency is inversely proportional to, echoed signal is directly proportional to measured target distance to the phase differential of reference signal).
Claims (7)
1. pulse/phase place integral type laser range finder, is characterized in that: comprise the double mode modulation circuit of Laser emission pulse/continuous wave and receive the double mode demodulator circuit of signal pulse laser flying time/phase differential; The double mode modulation circuit of Laser emission pulse/continuous wave comprises narrow pulse generating circuit, sine wave generating circuit, analog switch A, semiconductor laser, transmitting mirror, reception mirror, PIN detector, APD detector, operational amplifier A, operational amplifier B; Narrow pulse generating circuit, sine wave generating circuit are connected with semiconductor laser by analog switch A; Laser one tunnel of semiconductor laser transmitting is inputted APD detector through transmitting mirror, measurement target, reception mirror after receiving, and after operational amplifier B amplifies, exports echoed signal; Another road input of the laser of semiconductor laser transmitting PIN detector is exported reference signal after operational amplifier A is amplified; Receive the double mode demodulator circuit of signal pulse laser flying time/phase differential and comprise local oscillator sine wave generating circuit, analog switch B, mixing and filtering circuit, analog switch C, two-way high-speed comparator, time interval measuring circuit; Analog switch B receives reference signal and the echoed signal that the double mode modulation circuit of Laser emission pulse/continuous wave produces, and analog switch B can switch to analog switch C and be connected, and also can after mixing and filtering circuit, be connected with analog switch C; Analog switch C is connected with two-way high-speed comparator, and two-way high-speed comparator is connected with time interval measuring circuit.
2. pulse/phase place integral type laser range finder according to claim 1, is characterized in that: described narrow pulse generating circuit is the large current, narrow pulse generating circuit based on CPLD programming device and snowslide pipe, as the signal source of pulsed modulation.
3. pulse/phase place integral type laser range finder according to claim 1, it is characterized in that: described sine wave generating circuit is the sine wave generating circuit based on Direct Digital Synthesis-DDS principle, sinusoidal signal is amplified as modulated continuous wave signal source through 7 rank ellipse filtering circuits and power amplification circuit.
4. pulse/phase place integral type laser range finder according to claim 1, is characterized in that: described analog switch A, analog switch B, analog switch C are the analog switch of Low ESR, high-isolation.
5. pulse/phase place integral type laser range finder according to claim 1, it is characterized in that: under narrow pulse generating circuit, two kinds of patterns of sine wave generating circuit, signal is all that the light intensity of laser is modulated, the laser pulse of high-peak power, narrow pulsewidth is sent in drive laser work, or the sinusoidal wave laser of setpoint frequency.
6. pulse/phase place integral type laser range finder according to claim 1, it is characterized in that: under pulse ranging pattern, while being pulse generating circuit work, by single-chip microcomputer, operate control, when selecting laser instrument driving source passage, by two-stage analog switch B, analog switch C is with reference to signal, the direct gating of echoed signal is to two-way high-speed comparator, by wave shaping, it is the step signal that rising edge is steeper, by follow-up high precision time interval measurement circuit measuring, go out reference signal and the laser flying time interval corresponding to echoed signal again, be multiplied by the light velocity and draw tested distance.
7. pulse/phase place integral type laser range finder according to claim 1, it is characterized in that: under phase ranging pattern, while being sine wave generating circuit work, before laser works, by two-stage analog switch B, analog switch C, carry out channel selecting, with reference to signal and echoed signal, switch to mixing and filtering circuit, the output of mixing and filtering circuit is transferred to two-way high-speed comparator input end, when starting laser instrument sine wave generating circuit, start the local oscillator sine wave generating circuit with certain frequency difference, when mixing and filtering circuit receives reference signal, after echoed signal, carry out mixing and filtering with local oscillation signal respectively, the entrained phase information of high-frequency modulation signal is demodulated to low-frequency sine signal, again by the two-way high-speed comparator of rear class, it is poor that time interval measuring circuit is measured signal time, as division, obtain the poor ratio of corresponding phase with the frequency difference cycle, do multiplication with the corresponding survey chi of selected modulating frequency constant and can obtain tested distance.
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| CN201320600391.1U CN203502587U (en) | 2013-09-25 | 2013-09-25 | Pulse/phase integrated laser range finder |
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104076367A (en) * | 2014-07-14 | 2014-10-01 | 北京航空航天大学 | Phase-type laser distance-measurement system and method |
| CN104459710A (en) * | 2013-09-25 | 2015-03-25 | 北京航天计量测试技术研究所 | Pulse/phase integrated laser range finder |
| CN106054204A (en) * | 2016-07-26 | 2016-10-26 | 北京邮电大学 | Long distance and high accuracy oriented compound laser range finding method and system |
| CN107144850A (en) * | 2017-03-23 | 2017-09-08 | 苏州矗联电子技术有限公司 | A kind of high accuracy, the distance-finding method of wide-range and system |
| CN107607962A (en) * | 2017-09-22 | 2018-01-19 | 北京航天计量测试技术研究所 | A kind of method for improving phase laser distance measurement frequency |
| CN108169755A (en) * | 2017-12-14 | 2018-06-15 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of High Precision Long-distance laser range finder and distance measuring method |
| CN108594204A (en) * | 2018-06-15 | 2018-09-28 | 北京航空航天大学 | A kind of high accuracy remote narrow-pulse laser range unit |
| CN108646230A (en) * | 2018-05-16 | 2018-10-12 | 北京观详光电技术有限公司 | A kind of hybrid Doppler lidar and its application method |
| CN109164457A (en) * | 2018-10-15 | 2019-01-08 | 青岛市光电工程技术研究院(中国科学院光电研究院青岛光电工程技术研究中心) | Laser ranging system and range accuracy modification method |
| CN110658510A (en) * | 2018-06-28 | 2020-01-07 | 北京瑞特森传感科技有限公司 | Laser radar and ranging method |
| CN112904354A (en) * | 2021-01-22 | 2021-06-04 | 西安应用光学研究所 | High-precision laser ranging distance simulation device |
-
2013
- 2013-09-25 CN CN201320600391.1U patent/CN203502587U/en not_active Expired - Lifetime
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104459710A (en) * | 2013-09-25 | 2015-03-25 | 北京航天计量测试技术研究所 | Pulse/phase integrated laser range finder |
| CN104076367A (en) * | 2014-07-14 | 2014-10-01 | 北京航空航天大学 | Phase-type laser distance-measurement system and method |
| CN106054204A (en) * | 2016-07-26 | 2016-10-26 | 北京邮电大学 | Long distance and high accuracy oriented compound laser range finding method and system |
| CN107144850A (en) * | 2017-03-23 | 2017-09-08 | 苏州矗联电子技术有限公司 | A kind of high accuracy, the distance-finding method of wide-range and system |
| CN107607962A (en) * | 2017-09-22 | 2018-01-19 | 北京航天计量测试技术研究所 | A kind of method for improving phase laser distance measurement frequency |
| CN108169755A (en) * | 2017-12-14 | 2018-06-15 | 中国航空工业集团公司洛阳电光设备研究所 | A kind of High Precision Long-distance laser range finder and distance measuring method |
| CN108646230B (en) * | 2018-05-16 | 2020-12-29 | 北京观详光电技术有限公司 | Hybrid Doppler laser radar and use method thereof |
| CN108646230A (en) * | 2018-05-16 | 2018-10-12 | 北京观详光电技术有限公司 | A kind of hybrid Doppler lidar and its application method |
| CN108594204A (en) * | 2018-06-15 | 2018-09-28 | 北京航空航天大学 | A kind of high accuracy remote narrow-pulse laser range unit |
| CN110658510A (en) * | 2018-06-28 | 2020-01-07 | 北京瑞特森传感科技有限公司 | Laser radar and ranging method |
| CN110658510B (en) * | 2018-06-28 | 2023-01-10 | 北京瑞特森传感科技有限公司 | Laser radar and ranging method |
| CN109164457A (en) * | 2018-10-15 | 2019-01-08 | 青岛市光电工程技术研究院(中国科学院光电研究院青岛光电工程技术研究中心) | Laser ranging system and range accuracy modification method |
| CN112904354A (en) * | 2021-01-22 | 2021-06-04 | 西安应用光学研究所 | High-precision laser ranging distance simulation device |
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