CN102279391A - Doppler wind-measuring laser radar system - Google Patents

Abstract

The invention discloses a Doppler wind-measuring laser radar system. A small part of laser signals emitted by an emission system enters a lock channel of an FP (Fabry-Perot) etalon and a first analogue detector for detecting the laser signals through a lock channel light path in a light path receiving system. The laser signals entering the lock channel of the FP etalon are detected by a second analogue detector. The laser signals detected by the first analogue detector and the second analogue detector are acquired by an analogue acquisition card and sent to a first control system of a control system. The first control system is used for processing the received laser signals acquired by the analogue acquisition card, obtaining an emission laser frequency and the transmittance of the lock channel, and adjusting the cavity length of the EP etalon according to the transmittance of the lock channel, therefore, the emission laser frequency is locked at the intersection of two signal channel transmittances of the EP etalon; the emission laser frequency and the position of the EP etalon can be locked in real time; and the measurement precision is increased.

Description

The Doppler anemometry laser radar system

Technical field

The application relates to the laser radar technique field, particularly relates to the Doppler anemometry laser radar system.

Background technology

The Doppler anemometry laser radar system adopts the direct detection method, reflects the wind speed of atmosphere by the group velocity of atmospheric molecule.Its course of work is: the emission coefficient in the Doppler anemometry laser radar system is launched laser signal to atmosphere, and laser signal runs into atmospheric molecule and produces the Rayleigh back scattering, and Rayleigh back scattering atmosphere echoed signal is received system and receives.If atmospheric molecule produces motion because of wind, the frequency of the atmosphere echoed signal that receives of receiving system promptly produces Doppler shift with respect to the frequency shift of emission coefficient emitted laser signal so.After receiving system detects the Doppler shift that laser produces because of atmospheric molecule motion, draw the size of wind speed, utilize the multi-beam principle to obtain horizontal wind speed again by complementary operation.

Above-mentioned direct detection method is to measure the optimal path of the Doppler shift of upper atmosphere, so-called direct detection method, be meant direct measurement atmosphere echoed signal, and utilize optical detection elements that the atmosphere echoed signal that receives is carried out strength investigation, utilize Strength Changes to be finally inversed by a kind of method of Doppler frequency.At present, adopting more optical detection elements in the world is FP (Fabry-Perot, Fabry-Perot) etalon, this FP etalon utilizes the relation of the transmitance of etalon with frequency change, thereby the Strength Changes that detects the atmosphere echoed signal obtains Doppler shift, thereby is finally inversed by radially wind speed.

At present, binary channels FP etalon adopts the Doppler shift of dual edge technology atmospheric sounding back scattering laser, yet, the shoot laser frequency of emission laser can't guarantee to be locked in the place, point of crossing of two signalling channel transmitances of FP etalon in the dual edge technology, promptly can't realize the real-time lock of shoot laser frequency and FP etalon position, thereby reduce measuring accuracy.

Summary of the invention

In view of this, the embodiment of the present application provides a kind of Doppler anemometry laser radar system, to solve the real-time lock that can't realize shoot laser frequency and FP etalon position in the prior art, the problem of measuring accuracy reduction.Technical scheme is as follows:

The embodiment of the present application provides a kind of Doppler anemometry laser radar system, comprise: emission coefficient, be used to receive scanning system, receiving system and the control system of Rayleigh back scattering atmosphere echoed signal, described receiving system comprises: receiving light path system, the FP etalon that comprises two signalling channels and a locking channel and detection acquisition system, wherein:

Described receiving light path system comprises locking channel light path, two relatively independent signalling channel light paths, first analog prober, second analog prober, first photon counting detector, second photon counting detector and three-photon digital detector, wherein:

The fraction laser signal of emission coefficient emission, the described locking channel light path of process enters the locking channel of FP etalon respectively and to first analog prober that laser signal is surveyed, the laser signal that enters FP etalon locking channel is surveyed by second analog prober;

The Rayleigh back scattering atmosphere echoed signal that scanning system receives, enter two signalling channels of FP etalon and first photon counting detector that Rayleigh back scattering atmosphere echoed signal is surveyed respectively through two signalling channel light paths, the Rayleigh backscatter signal that enters two signalling channels of FP etalon is surveyed by second photon counting detector and three-photon digital detector;

Described detection acquisition system comprises: analog acquisition card and three photon counting cards; Described three photon counting cards link to each other with the three-photon digital detector with first photon counting detector, second photon counting detector respectively, are used for gathering the atmosphere echoed signal that enters detector; Described analog acquisition card is two passage A/D capture cards, links to each other with second analog prober with first analog prober respectively, is used for gathering the laser signal that enters analog prober;

Described control system comprises first control system, be used to receive the laser signal of three photon counting cards and the collection of analog acquisition card, draw the shoot laser frequency, the relative frequency of the transmitance of locking channel and Rayleigh back scattering atmosphere echoed signal, relative frequency according to shoot laser frequency and Rayleigh back scattering atmosphere echoed signal, draw the Doppler shift of laser signal and be finally inversed by radially wind speed, while is according to the transmitance of locking channel, the chamber of adjusting the FP etalon is long, makes the shoot laser frequency be positioned at the place, point of crossing of two margin signal passages of etalon all the time.

Preferably, described receiving light path system specifically comprises:

The fraction laser signal of emission coefficient emission is coupled into the expansion of first collimating mirror through optical fiber and restraints into parallel beam, filter bias light by first interference filter, the laser signal of removal bias light enters first beam splitter through the reflected light of first catoptron, the reflected light of first beam splitter enters described first analog prober through first convergent lens, the transmitted light of first beam splitter enters the locking channel of FP etalon, the emergent light that penetrates from locking channel by second mirror reflects after, enter described second analog prober through second convergent lens;

The Rayleigh back scattering atmosphere echoed signal that scanning system receives is coupled into the expansion of second collimating mirror through optical fiber and restraints into parallel beam, parallel beam filters bias light by second interference filter after through the 3rd mirror reflects, the echoed signal of removing bias light enters second beam splitter, the transmitted light of second beam splitter is the 4th catoptron and enter described first photon counting detector through the 3rd convergent lens successively, the reflected light of second beam splitter is beamed into two signalling channels that two bundle directional lights enter the FP etalon respectively through beam splitter prism, the laser echo signal of a signalling channel enters described second photon counting detector through the 5th catoptron and the 4th convergent lens successively, and the laser echo signal of another signalling channel enters described three-photon digital detector through the 6th catoptron and the 5th convergent lens successively.

Preferably, described emission coefficient comprises: laser instrument, beam splitter, beam expanding lens and catoptron;

Laser instrument emitted laser signal is through behind the beam splitter, reflected light enters described receiving system, transmitted light enters described beam expanding lens, described beam expanding lens is used to compress the angle of divergence of described laser instrument emission laser signal, and the laser signal process mirror reflects after emission angle is compressed is to described scanning system.

Preferably, described scanning system comprises: telescope and controlled in wireless scanister;

Described telescope transceiver system emitted laser signal, and send to described wireless scanister;

Described wireless scanister reflexes to atmosphere with laser signal, receives Rayleigh back scattering atmosphere echoed signal simultaneously and Rayleigh back scattering atmosphere echoed signal is reflexed to described telescope, is coupled to receiving system by described telescope through optical fiber.

Preferably, telescope is the Zigzag type Cassegrain telescope; Effective clear aperture of described Zigzag type Cassegrain telescope is 450mm; The focal length 1m of system; Central obscuration is than＜15%; Adopt the optical fiber of core diameter 200m, numerical aperture 0.22 to receive laser echo signal, the field angle of reception is 0.2mrad; Minute surface plating emissivity is greater than 98% 355nm wavelength deielectric-coating; Have tight adjustment support in the secondary mirror mechanism.

Preferably, described controlled in wireless scanister adopts the biplane Scan Architecture, has horizontal scanning and pitching scan function; Sweep limit is 0～360 ° of scan round of horizontal direction, 0～90 ° of vertical direction; Effective clear aperature of the level crossing of scanning card is 450mm, emission minute surface plating 355nm dielectric reflection film, and reflectivity is 99%355nm; Adopt full-closed structure, the packaged glass bore is 450mm, thickness 25mm, and the plating high antireflection film, transmitance is 99%355nm; Scanning angle resolution is 36 "; Angular scanning rate is 15 °/s; The scan angle acceleration is 3 °/s.

Preferably, described control system also comprises: by the scanning device controller of RS232 serial ports and the communication of described controlled in wireless scanister, be used to adjust the orientation of described controlled in wireless scanister.

Preferably, described control system also comprises:

Gating circuit, be used to send trigger pip to described first analog prober, second analog prober, first photon counting detector, second photon counting detector, three-photon digital detector and detection acquisition system, control described first analog prober, second analog prober, first photon counting detector, second photon counting detector, three-photon digital detector and survey acquisition system work.

Preferably, described beam expanding lens is the Galileo beam expanding lens.

Preferably, two signalling channels of described FP etalon are positioned on the center line of this FP etalon bore side by side, and described locking channel is positioned at the top of described signalling channel, and the diameter of this locking channel is less than the diameter of described signalling channel.

Use technique scheme, the fraction laser signal of emission coefficient emission enters the locking channel of FP etalon by the locking channel light path in the receiving light path system and to first analog prober that laser signal is surveyed, the laser signal that enters FP etalon locking channel is surveyed by second analog prober.The laser signal that first analog prober and second analog prober detect simulated the capture card collection and sends to first control system of control system.First control system is handled the laser signal of the analog acquisition card collection that receives, draw the transmitance of shoot laser frequency and locking channel, transmitance according to locking channel, the chamber of adjusting the FP etalon is long, make the point of crossing place of outgoing laser frequency lock in two signalling channel transmitances of FP etalon, realize the real-time lock of shoot laser frequency and FP etalon position, improved measuring accuracy.

Description of drawings

In order to be illustrated more clearly in the embodiment of the present application or technical scheme of the prior art, to do to introduce simply to the accompanying drawing of required use in embodiment or the description of the Prior Art below, apparently, the accompanying drawing that describes below only is some embodiment that put down in writing among the application, for those of ordinary skills, under the prerequisite of not paying creative work, can also obtain other accompanying drawing according to these accompanying drawings.

A kind of structural representation of the Doppler anemometry laser radar system that Fig. 1 provides for the embodiment of the present application;

Fig. 2 utilizes the wind speed that the Doppler anemometry laser radar system records and the contrast profile of balloon;

Fig. 3 utilizes the wind direction that the Doppler anemometry laser radar system records and the contrast profile of balloon;

Fig. 4 utilizes the Doppler anemometry laser radar system to record wind profile figure and wind profile radar record wind field profile figure at 00:20AM on 25Nov 2009 comparison diagram;

Fig. 5 utilizes the Doppler anemometry laser radar system to record wind profile figure and wind profile radar record wind field profile figure at 00:40AM on 25Nov 2009 comparison diagram;

Fig. 6 is the structural representation of receiving light path system in the Doppler anemometry laser radar system shown in Figure 1;

Fig. 7 is the signal graph of the echo laser that photon counting detector is surveyed in the receiving light path system shown in Figure 6;

Fig. 8 is four wave beam method synoptic diagram;

The another kind of structural representation of the Doppler anemometry laser radar system that Fig. 9 provides for the embodiment of the present application.

Embodiment

For above-mentioned purpose, the feature and advantage that make the application can become apparent more, the application is described in further detail below in conjunction with the drawings and specific embodiments.

An embodiment

See also Fig. 1, Fig. 1 is the structural representation of a kind of Doppler anemometry laser radar of the embodiment of the present application system, comprising: emission coefficient 100, scanning system 200, receiving system 300 and control system 400.Wherein: emission coefficient 100 emission laser signals, the sub-fraction laser signal directly enters receiving system 300 through the optical fiber coupling, most of laser signal enters scanning system 200, scanning system 200 is injected atmosphere with laser signal, receives the Rayleigh back scattering atmosphere echoed signal of returning through atmosphere simultaneously.Rayleigh back scattering atmosphere echoed signal is received by scanning system 200 and is coupled into receiving system 300 by optical fiber.

Receiving system 300 comprises: receiving light path system, the FP etalon 304 that comprises 301,302 and locking channels 303 of two signalling channels and detection acquisition system, wherein:

The receiving light path system comprises locking channel light path 305, two relatively independent signalling channel light paths 306 and 307, first analog prober 308, second analog prober 309, first photon counting detector 310, second photon counting detector 311 and the three-photon digital detector 312, wherein: locking channel light path 305 communicates with the locking channel 303 of FP etalon 304, signalling channel light path 306 communicates with the signalling channel 301 of FP etalon 304, and signalling channel light path 307 communicates with signalling channel 301.

The fraction laser signal of emission coefficient 300 emissions is directly entered the locking channel light path 305 of receiving system 300 by the optical fiber coupling, and enter the locking channel 303 of FP etalon 304 respectively and to first analog prober 308 that laser signal is surveyed, the laser signal that enters FP etalon 304 locking channels 303 is surveyed by second analog prober 309.

The Rayleigh back scattering atmosphere echoed signal that scanning system 200 receives is coupled to the signalling channel light path 306 of receiving system 300 by optical fiber, and enters the signalling channel 301 of FP etalon 304 and first photon counting detector 310 that Rayleigh back scattering atmosphere echoed signal is surveyed.Simultaneously, the Rayleigh back scattering atmosphere echoed signal of receiving system 300 receptions is also passed through the signalling channel 302 that another signalling channel light path 307 enters FP etalon 304.Entering two signalling channels 301 of FP etalon 304 and 302 Rayleigh back scattering atmosphere echoed signal is surveyed by second photon counting detector 311 and three-photon digital detector 312.

The detection acquisition system comprises: analog acquisition card 313 and three photon counting cards 314,315 and 316.Wherein:

Photon counting card 314 links to each other with first photon counting detector 310, photon counting card 315 links to each other with second photon counting detector 311, photon counting card 316 links to each other with three-photon digital detector 312. and three photon counting cards are gathered the atmosphere echoed signal that coupled photon counting detector detects respectively, and the atmosphere echoed signal that collects is sent to control system 400.

Analog acquisition card 313 is two-way A/D capture cards, links to each other with second analog prober 309 with first analog prober 308 respectively, is used for gathering the laser signal that enters analog prober, and the laser signal that collects is sent to control system 400.

Control system 400 comprises first control system 401, be used to receive the laser signal of three photon counting cards and 313 collections of analog acquisition card, draw the shoot laser frequency, the relative frequency of the transmitance of locking channel and Rayleigh back scattering atmosphere echoed signal, relative frequency according to shoot laser frequency and Rayleigh back scattering atmosphere echoed signal draws Doppler shift and is finally inversed by radially wind speed.The Doppler shift that draws as first control system 401 is Δ v, and the laser signal wavelength is λ, and radially wind speed then is: λ * Δ v/2.

Simultaneously, because the influence of device heating and environment temperature, the centre frequency of FP etalon 304 can produce frequency drift along with the change of environment temperature, make the shoot laser frequency can't be locked in the place, point of crossing of 304 two signalling channel transmitances of FP etalon, the doppler shift data that causes measuring exists uncertainty and error.First control system 401 is according to the transmitance of locking channel, and the chamber of adjusting FP etalon 304 is long, guarantees the point of crossing place of shoot laser frequency real-time lock in 304 two signalling channel transmitances of FP etalon, improves measuring accuracy.

See also Fig. 2 to Fig. 5, wherein Fig. 2 utilizes the wind speed that the Doppler anemometry laser radar system records and the contrast profile synoptic diagram of balloon, the air speed data that DWL among the figure (doppler wind lidar, Doppler anemometry laser radar) records for the Doppler anemometry laser radar system that utilizes the application to provide; Balloon is the air speed data that balloon records, and can see very clearly that by figure both can be good at meeting.Fig. 3 utilizes the wind direction that the Doppler anemometry laser radar system records and the contrast outline line synoptic diagram of balloon, the wind direction data that DWL records for the Doppler anemometry laser radar system that utilizes the application and provide; Balloon is the wind direction data that balloon records, and can see very clearly that by figure both can be good at meeting.

Fig. 4 and Fig. 5 are under the less situation of laser signal energy and different time sections, the contrast of the wind field profile figure that wind profile figure that the Doppler anemometry laser radar system that utilizes the application to provide records and wind profile radar system record, Fig. 4 is the data that 00:20AM on 25Nov 2009 records, Fig. 5 is the data that record at 00:40AM on 25Nov 2009, the air speed data that DWL records for the Doppler anemometry laser radar system that utilizes the application and provide among two figure, the wind field speed data of WPR (wind profile radar, microwave wind profile radar) for utilizing wind profile radar to record.Two kinds of profile basically identicals that metering system obtains as can be seen from two figure illustrate that the Doppler anemometry laser radar system that the application provides also can measure the Rayleigh back scattering atmosphere echoed signal of low level air based on aerosol scattering.

Use technique scheme, the fraction laser signal of emission coefficient 100 emissions enters the locking channel 303 of FP etalon 304 by the locking channel light path 305 in the receiving light path system and to first analog prober 308 that laser signal is surveyed, the shoot laser signal that enters FP etalon 304 locking channels 303 is surveyed by second analog prober 309.The laser signal that first analog prober 308 and second analog prober 309 detect simulated first control system 401 that control system was gathered and sent to capture card 313.The laser signal of the analog acquisition card collection that 401 pairs of first control system receive is handled, draw the transmitance of shoot laser frequency and locking channel, transmitance according to locking channel, the chamber of adjusting FP etalon 304 is long, make the point of crossing place of outgoing laser frequency lock in 304 two signalling channel transmitances of FP etalon, realize the real-time lock of shoot laser frequency and FP etalon 304 positions, improved measuring accuracy.

Another embodiment

Be provided with the basic optical device in the locking channel light path 305 of receiving light path system, two relatively independent signalling channel light paths 306 and 307 in the foregoing description, the atmosphere echoed signal that enters receiving system is handled.Structural representation is specially as shown in Figure 6:

The fraction laser signal of emission coefficient 100 emissions is coupled into first collimating mirror L1 expansion through optical fiber 1 and restraints into parallel beam, filter bias light by the first interference filter F1, the laser signal of removal bias light enters the first beam splitter BS1 through the reflected light of first mirror M 1, the reflected light of the first beam splitter BS1 enters first analog prober 308 through the first convergent lens N1, the transmitted light of first beam splitter enters the locking channel 303 of FP etalon 304, the emergent light that penetrates from locking channel 303 by 2 reflections of second mirror M after, enter described second analog prober 309 through the second convergent lens N2.

The Rayleigh back scattering atmosphere echoed signal that scanning system 200 receives is coupled into second collimating mirror L2 expansion through optical fiber 2 and restraints into parallel beam, parallel beam filters bias light through the 3rd mirror M 3 reflection backs by the second interference filter F2, the atmosphere echoed signal of removing bias light enters the second beam splitter BS2, the reflected light that the transmitted light of the second beam splitter BS2 enters first photon counting detector, 310, the second beam splitter BS2 through the 4th mirror M 4 and the 3rd convergent lens N3 successively is beamed into two signalling channels 301 and 302 that two bundle directional lights enter FP etalon 304 respectively through beam splitter prism P.The atmosphere echoed signal of signalling channel 301 enters second photon counting detector 311 through the 5th mirror M 5 and the 4th convergent lens N4 successively, and the atmosphere echoed signal of another signalling channel 302 enters three-photon digital detector 312 through the 6th mirror M 6 and the 5th convergent lens N5 successively.

What first photon counting detector 310, second photon counting detector 311 and three-photon digital detector 312 adopted is the single photon counting form, can measure the faint atmosphere echoed signal of returning through upper atmosphere, as shown in Figure 7, as can be seen from the figure in the atmosphere echoed signal that also has basically about 60 kilometers about 8 photons, and then the measuring height that improves, increased the performance of system.

Above-mentioned receiving system 300 is placed in one 19 inches the rack.Because the centre frequency of FP etalon 304 can produce frequency drift along with the change of environment temperature, and first analog prober 308, second analog prober 309, first photon counting detector 310, second photon counting detector 311, three-photon digital detector 312, when being stuck in work, analog acquisition card 313 and three photon countings can generate heat, therefore the rack that is used to place receiving system 300 is divided into two parts, wherein a part is placed and is arranged on locking channel light path 305, basic optical device and FP etalon 304 in two signalling channel light paths 306 and 307, another part is placed detector, numbered card, analog acquisition card and optical fiber socket.Be connected in the optical fiber 1 of emission coefficient 100 and receiving system 300, the optical fiber 2 of scanning system 200 and receiving system 300 inserts respectively in the different optical fiber sockets, adopts optical fiber to connect, and improves system flexibility and stability.

Doppler anemometry laser radar system shown in Figure 1, emission coefficient 100 comprises: laser instrument 101, beam splitter 102, beam expanding lens 103 and catoptron 104.

Laser instrument 101 emitted laser signals are through behind the beam splitter 102, and reflected light is coupled into receiving system 300 through coupled optical fiber, and transmitted light enters beam expanding lens 103.Beam expanding lens 103 is used to compress the angle of divergence of 3 laser signal devices, 101 emitted laser signals, and the laser signal after the emission angle compression is reflexed to scanning system 200 through catoptron 104.

What laser instrument 101 adopted is the pouring-in lamp pump of U.S. Continuum company seed Nd:YAG laser instrument, and behind the frequency tripling, single pulse energy is 400mJ, and pulse repetition rate is 30Hz, and pulsewidth is 3～7ns, and beam divergence angle is 0.5mrad.Transmitted light shield scattered light, and then raising enters the laser signal of scanning system 200 through beam expanding lens 103 back light beam complete closed.Beam expanding lens 103 is the Galileo beam expanding lens simultaneously, can avoid laser signal to cross strong damage device.

Scanning system 200 comprises: telescope 201 and controlled in wireless scanister 202.Telescope 201 transceiver systems 100 emitted laser signals, by controlled in wireless scanister 202 laser signal is reflexed to atmosphere, the Rayleigh back scattering atmosphere echoed signal that produces through atmosphere is received by telescope 201 through controlled in wireless scanister 202 reflection backs once more.Telescope 202 is coupled into receiving system 300 with Rayleigh back scattering atmospheric signal through coupled optical fiber.

Telescope 201 is the Zigzag type Cassegrain telescope.Effective clear aperture of Zigzag type Cassegrain telescope is 450mm; The focal length 1m of system; Central obscuration is than＜15%; Adopt the optical fiber of core diameter 200m, numerical aperture 0.22 to receive laser signal, the field angle of reception is 0.2mrad; Minute surface plating emissivity is greater than 98% 355nm wavelength deielectric-coating; Have tight adjustment support in the secondary mirror mechanism.Because the field angle of the reception of Zigzag type Cassegrain telescope is 0.2mrad, so beam expanding lens 103 emission field angle are less than 0.1mrad.When beam expanding lens 103 enlarges x times with light beam, 1/x times of its emission angle compression, therefore, beam expanding lens 103 will carry out 10 times to the reflected light that receives and expand bundle.

Controlled in wireless scanister 202 adopts the biplane Scan Architecture, has horizontal scanning and pitching scan function; Sweep limit is 0～360 ° of scan round of horizontal direction, 0～90 ° of vertical direction; Effective clear aperature of the level crossing of scanning card is 450mm, emission minute surface plating 355nm dielectric reflection film, and reflectivity is 99%355nm; Adopt full-closed structure, the packaged glass bore is 450mm, thickness 25mm, and the plating high antireflection film, transmitance is 99%355nm; Scanning angle resolution is 36 "; Angular scanning rate is 15 °/s; The scan angle acceleration is 3 °/s.Utilize the packaged glass both can dust protection, can allow the radar system can all weather operations again.

The Doppler anemometry laser radar system that the embodiment of the present application provides adopts four wave beam methods to measure horizontal wind speed.So-called four wave beam methods are to measure the radially wind speed of four direction respectively, promptly measure 0 degree, 90 degree, 180 degree and 270 degree directions respectively and get radially wind speed, utilize the radially wind speed of four direction to be finally inversed by horizontal wind speed then.As shown in Figure 8, be the positive dirction of x with positive east, the positive north is the positive dirction (wind direction initial direction) of y, directly over be the positive dirction of z, φ is a launching elevation, the radial velocity of four direction is respectively: V _r, V _RN, V _RSAnd V _REThen: $V=\stackrel{\→}{V_{x}i}+\stackrel{\→}{V_{y}j}+\stackrel{\→}{V_{z}k}$

$\left\{\begin{array}{c}\stackrel{\→}{r_N}=\sin \mathrm{\φ}\stackrel{\→}{j}+\cos \mathrm{\φ}\stackrel{\→}{k}\\ \stackrel{\→}{r_E}=\sin \mathrm{\φ}\stackrel{\→}{i}+\cos \mathrm{\φ}\stackrel{\→}{k}\\ \stackrel{\→}{r_S}=-\sin \mathrm{\φ}\stackrel{\→}{j}+\cos \mathrm{\φ}\stackrel{\→}{k}\\ \stackrel{\→}{r_W}=-\sin \mathrm{\φ}\stackrel{\→}{i}+\cos \mathrm{\φ}\stackrel{\→}{k}\end{array}\right.$

Then

$\left\{\begin{array}{c}{V}_{\mathrm{rN}}=V_y\sin \mathrm{\φ}+V_z\cos \mathrm{\φ}\\ V_{\mathrm{rE}}=V_x\sin \mathrm{\φ}+V_z\cos \mathrm{\φ}\\ V_{\mathrm{rS}}=-V_y\sin \mathrm{\φ}+V_z\cos \mathrm{\φ}\\ V_{\mathrm{rW}}=-V_x\sin \mathrm{\φ}+V_z\cos \mathrm{\φ}\end{array}\right.$

$V_y=\frac{V_{\mathrm{rN}}-{\mathrm{<figure-callout\; id="2"\; label="V\; rS"\; filenames="HDA0000069991460000041.png,HDA0000069991460000051.png"\; state="\{\{state\}\}">V</figure-callout>}}_{\mathrm{rS}}}{2\sin \mathrm{\&phi;}},$ $V_x=\frac{V_{\mathrm{rE}}-{\mathrm{<figure-callout\; id="2"\; label="V\; rW"\; filenames="HDA0000069991460000041.png,HDA0000069991460000051.png"\; state="\{\{state\}\}">V</figure-callout>}}_{\mathrm{rW}}}{2\sin \mathrm{\&phi;}},$

So horizontal wind speed is: $V_h=\sqrt{{\left(V_x\right)}^2+{\left(V_y\right)}^2}$

Horizontal wind direction is: $\mathrm{\&gamma;}=\left\{\begin{array}{cc}\arctan (V_x/V_y)\&CenterDot;180/\mathrm{\&pi;}& V_x>0,V_y>0\\ 180+\arctan (V_x/V_y)\&CenterDot;180/\mathrm{\&pi;}& V_y<0\\ 360+\arctan (V_x/V_y)\&CenterDot;180/\mathrm{\&pi;}& V_x<0,V_y>0\\ 90& V_x>0,V_y=0\\ 270& V_x<0,V_y=0\end{array}\right.$

In order to realize surveying the radially wind speed of 0 degree, 90 degree, 180 degree and 270 degree four directions, laser instrument 101 and controlled in wireless scanister 202 are after finishing 0 degree orientation measurement, scanning device controller 402 control controlled in wireless scanister 202 revolve and turn 90 degrees, and laser instrument 101 also revolves and turn 90 degrees the radially measuring wind speed that carries out 90 degree directions simultaneously.By that analogy.Laser instrument 101 is worked all the time in rotary course, because want the real-time locking of carrying out FP etalon 304 and shoot laser frequency, to guarantee the point of crossing place of shoot laser frequency real-time lock, improve measuring accuracy in 304 two signalling channel transmitances of FP etalon.

Controlled in wireless scanister 202 can be emitted to atmosphere with laser signal according to mode 0 degree, 90 degree, 180 degree and 270 degree by user's manual operation rotation, certainly, can also adopt automated manner to realize.Doppler anemometry laser radar system shown in Figure 9 is on the basis of Doppler anemometry laser radar system shown in Figure 1, in control system 400, increased scanning device controller 402, and carry out communication by the RS232 serial ports between the controlled in wireless scanister 202, be used to adjust the orientation of controlled in wireless scanister 202, make controlled in wireless scanister 202 rotate to 0 degree, 90 degree, 180 degree and 270 degree automatically and be emitted to atmosphere.

The Doppler anemometry laser radar system that the embodiment of the present application provides adopts four wave beam methods to measure horizontal wind speed with respect to existing three wave beam methods, has improved the measuring accuracy of wind speed.Measuring wind speed accuracy computation formula is:

$\mathrm{var}\left[\stackrel{\&RightArrow;}{u}\right],\mathrm{var}\left[\stackrel{\&RightArrow;}{v}\right],\mathrm{var}\left[\stackrel{\&RightArrow;}{w}\right]=[2/{\sin }^2\left(\mathrm{\&phi;}\right),2/{\sin }^2\left(\mathrm{\&phi;}\right),1/{\cos }^2\left(\mathrm{\&phi;}\right)]\frac{\mathrm{var}\left[V_r\right]}{N_{\mathrm{los}}}$

Wherein: var[V _r] being air speed error radially, Nlos is a numbers of beams, the four direction scanning survey that promptly adopts in the native system, Nlos=4 wherein, the many more measuring wind so of the direction of scanning survey precision is just big more as can be seen from above-mentioned formula, and error is just more little.So the Doppler anemometry laser radar system that the embodiment of the present application provides adopts four wave beam methods to measure horizontal wind speed with respect to existing three wave beam methods, has improved the measuring accuracy of wind speed.

In addition, control system 400 also comprises: gating circuit 403, by PCI (Peripheral Component Interconnect, the Peripheral Component Interconnect standard) with first analog prober 308, second analog prober 309, first photon counting detector 310, second photon counting detector 311, three-photon digital detector 312, survey acquisition system and scanning device controller 402 communications, be used to send trigger pip to first analog prober 308, second analog prober 309, first photon counting detector 310, second photon counting detector 311, three-photon digital detector 312 and detection acquisition system are controlled these equipment works.Wherein:

Gating circuit 403 is the outputs of eight passages, and promptly can export is exactly eight gate-control signals.First analog prober 308, second analog prober 309, first photon counting detector 310, second photon counting detector 311 and three-photon digital detector 312 shared one road gate-control signals in the embodiment of the present application, three photon collection cards use one road gate-control signal, and analog acquisition card 313 uses one road gate-control signal.Gate-control signal in the gating circuit 403 is that user oneself sets, and the output of gating circuit 403 needs and the output of laser instrument 101 is synchronous, to guarantee in real time synchronously.

Two signalling channels of above-mentioned FP etalon 304 are positioned on the center line of FP etalon 304 bores side by side, and locking channel 303 is positioned at the top of signalling channel, and the diameter of this locking channel 303 is less than the diameter of signalling channel.Because the bore of the locking channel 303 of FP etalon 304 dwindles, and then reduces the bore of FP etalon 304, has reduced the processing cost of FP etalon 304.And because one road independent locking channel light path 305 is led to the locking channel 303 of FP etalon 304, and the bore of locking channel 303 is less, and interference portion is less in the light path 3, and therefore, the receiving light path system is simpler, helps the adjusting of light path.

Each embodiment in this instructions all adopts the mode of going forward one by one to describe, identical similar part is mutually referring to getting final product between each embodiment, each embodiment stresses all is difference with other embodiment, those of ordinary skills promptly can understand and implement under the situation of not paying creative work.

The above only is the application's a embodiment; should be pointed out that for those skilled in the art, under the prerequisite that does not break away from the application's principle; can also make some improvements and modifications, these improvements and modifications also should be considered as the application's protection domain.

Claims (10)

1. Doppler anemometry laser radar system, comprise: emission coefficient, be used to receive scanning system, receiving system and the control system of Rayleigh back scattering atmosphere echoed signal, it is characterized in that, described receiving system comprises: receiving light path system, the FP etalon that comprises two signalling channels and a locking channel and detection acquisition system, wherein:

Described receiving light path system comprises locking channel light path, two relatively independent signalling channel light paths, first analog prober, second analog prober, first photon counting detector, second photon counting detector and three-photon digital detector, wherein:

The fraction laser signal of emission coefficient emission, the described locking channel light path of process enters the locking channel of FP etalon respectively and to first analog prober that laser signal is surveyed, the laser signal that enters FP etalon locking channel is surveyed by second analog prober;

The Rayleigh back scattering atmosphere echoed signal that scanning system receives, enter two signalling channels of FP etalon and first photon counting detector that Rayleigh back scattering atmosphere echoed signal is surveyed respectively through two signalling channel light paths, the Rayleigh backscatter signal that enters two signalling channels of FP etalon is surveyed by second photon counting detector and three-photon digital detector;

Described detection acquisition system comprises: analog acquisition card and three photon counting cards; Described three photon counting cards link to each other with the three-photon digital detector with first photon counting detector, second photon counting detector respectively, are used for gathering the atmosphere echoed signal that enters detector; Described analog acquisition card is two passage A/D capture cards, links to each other with second analog prober with first analog prober respectively, is used for gathering the laser signal that enters analog prober;

Described control system comprises first control system, be used to receive the laser signal of three photon counting cards and the collection of analog acquisition card, draw the shoot laser frequency, the relative frequency of the transmitance of locking channel and Rayleigh back scattering atmosphere echoed signal, relative frequency according to shoot laser frequency and Rayleigh back scattering atmosphere echoed signal, draw the Doppler shift of laser signal and be finally inversed by radially wind speed, while is according to the transmitance of locking channel, the chamber of adjusting the FP etalon is long, makes the shoot laser frequency be positioned at the place, point of crossing of two margin signal passages of etalon all the time.

2. Doppler anemometry laser radar according to claim 1 system is characterized in that, described receiving light path system specifically comprises:

The fraction laser signal of emission coefficient emission is coupled into the expansion of first collimating mirror through optical fiber and restraints into parallel beam, filter bias light by first interference filter, the laser signal of removal bias light enters first beam splitter through the reflected light of first catoptron, the reflected light of first beam splitter enters described first analog prober through first convergent lens, the transmitted light of first beam splitter enters the locking channel of FP etalon, the emergent light that penetrates from locking channel by second mirror reflects after, enter described second analog prober through second convergent lens;

The Rayleigh back scattering atmosphere echoed signal that scanning system receives is coupled into the expansion of second collimating mirror through optical fiber and restraints into parallel beam, parallel beam filters bias light by second interference filter after through the 3rd mirror reflects, the echoed signal of removing bias light enters second beam splitter, the transmitted light of second beam splitter is the 4th catoptron and enter described first photon counting detector through the 3rd convergent lens successively, the reflected light of second beam splitter is beamed into two signalling channels that two bundle directional lights enter the FP etalon respectively through beam splitter prism, the laser echo signal of a signalling channel enters described second photon counting detector through the 5th catoptron and the 4th convergent lens successively, and the laser echo signal of another signalling channel enters described three-photon digital detector through the 6th catoptron and the 5th convergent lens successively.

3. Doppler anemometry laser radar according to claim 1 system is characterized in that described emission coefficient comprises: laser instrument, beam splitter, beam expanding lens and catoptron;

Laser instrument emitted laser signal is through behind the beam splitter, reflected light enters described receiving system, transmitted light enters described beam expanding lens, described beam expanding lens is used to compress the angle of divergence of described laser instrument emission laser signal, and the laser signal process mirror reflects after emission angle is compressed is to described scanning system.

4. Doppler anemometry laser radar according to claim 3 system is characterized in that described scanning system comprises: telescope and controlled in wireless scanister;

Described telescope transceiver system emitted laser signal, and send to described wireless scanister;

Described wireless scanister reflexes to atmosphere with laser signal, receives Rayleigh back scattering atmosphere echoed signal simultaneously and Rayleigh back scattering atmosphere echoed signal is reflexed to described telescope, is coupled to receiving system by described telescope through optical fiber.

5. Doppler anemometry laser radar according to claim 4 system is characterized in that telescope is the Zigzag type Cassegrain telescope; Effective clear aperture of described Zigzag type Cassegrain telescope is 450mm; The focal length 1m of system; Central obscuration is than＜15%; Adopt the optical fiber of core diameter 200m, numerical aperture 0.22 to receive laser echo signal, the field angle of reception is 0.2mrad; Minute surface plating emissivity is greater than 98% 355nm wavelength deielectric-coating; Have tight adjustment support in the secondary mirror mechanism.

6. Doppler anemometry laser radar according to claim 4 system is characterized in that, described controlled in wireless scanister adopts the biplane Scan Architecture, has horizontal scanning and pitching scan function; Sweep limit is 0～360 ° of scan round of horizontal direction, 0～90 ° of vertical direction; Effective clear aperature of the level crossing of scanning card is 450mm, emission minute surface plating 355nm dielectric reflection film, and reflectivity is 99%355nm; Adopt full-closed structure, the packaged glass bore is 450mm, thickness 25mm, and the plating high antireflection film, transmitance is 99%355nm; Scanning angle resolution is 36 "; Angular scanning rate is 15 °/s; The scan angle acceleration is 3 °/s.

7. Doppler anemometry laser radar according to claim 4 system, it is characterized in that, described control system also comprises: by the scanning device controller of RS232 serial ports and the communication of described controlled in wireless scanister, be used to adjust the orientation of described controlled in wireless scanister.

8. Doppler anemometry laser radar according to claim 7 system is characterized in that described control system also comprises:

Gating circuit, be used to send trigger pip to described first analog prober, second analog prober, first photon counting detector, second photon counting detector, three-photon digital detector and detection acquisition system, control described first analog prober, second analog prober, first photon counting detector, second photon counting detector, three-photon digital detector and survey acquisition system work.

9. according to any described Doppler anemometry laser radar system of claim 4 to 8, it is characterized in that described beam expanding lens is the Galileo beam expanding lens.

10. according to any described Doppler anemometry laser radar system of claim 1 to 8, it is characterized in that, two signalling channels of described FP etalon are positioned on the center line of this FP etalon bore side by side, described locking channel is positioned at the top of described signalling channel, and the diameter of this locking channel is less than the diameter of described signalling channel.

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