CN102508225A - Double-shaft laser remote sensing instrument ground detection and calibration system and detection and calibration method - Google Patents

Abstract

The invention provides a double-shaft laser remote sensing instrument ground detection and calibration system, which comprises a simulation echo generator, a two-dimensional moving platform, a heavy-caliber long-focus collimator and a light beam quality analyzer. One side of the heavy-caliber long-focus collimator is provided with a beam splitter and a pyramid prism, and the other side of the heavy-caliber long-focus collimator is provided with a total-reflection mirror. The simulation echo generator is composed of a photolectric transducer, a time delay unit, an optical fiber output laser, optical fiber and an electronic control optical attenuator. The optical fiber output laser is connected with one end of the optical fiber, and the other end of the optical fiber is located on the other side of the heavy-caliber long-focus collimator. A port of the other end of the optical fiber is located on a focal plane of the heavy-caliber long-focus collimator and fixed on the two-dimensional moving platform. The detection and calibration system is capable of obtaining far-field light beam quality distribution and detectivity of the detected active and passive laser remote sensing instrument and is capable of obtaining geometric construction factors of the detected active and passive laser remote sensing instrument.

Description

Twin shaft laser remote sensing instrument ground detection scaling system and detection calibrating method

Technical field

The invention belongs to laser active remote sensing field of detecting; Relate to twin shaft laser remote sensing instrument ground detection scaling system, also relate to this system the systematic parameter-detectivity of main passive laser remote sensing instrument, the method that the far field beam quality distributes, the system geometries factor detects and demarcates.

Background technology

Since laser is born, the fast development of laser science technology.The laser remote sensing instrument has been widely used in research fields such as celestial body measurement, aerial target detection, Laser Atmospheric Transmission, global climate prediction, gasoloid radiation effect and atmospheric environment as a kind of active remote sensing Detection Techniques.The principle of work of laser remote sensing system is to get into atmosphere by the laser beam pulses that laser instrument sends; Receive the scatter echo signal that produces after laser beam and atmosphere or the irradiated object effect by telescope; And after optics light-splitting processing and photodetector system conversion; Input information treatment facility (being mostly computing machine) carries out data inversion to be handled, in the hope of obtaining information such as distance, spectrum, image.

Along with the expansion of laser remote sensing instrument application scope and the raising of application demand, people are also increasingly high to the detectivity and the system stability requirement of system, and this also has higher requirement to the ground calibration and the test performance of remote sensing system.The detectivity index of laser remote sensing instrument mainly comprises system's detection accuracy, accuracy, investigative range (maximum ranging, minimum ranging), resolution of ranging and detection probability (false alarm rate, false dismissed rate).Except detectivity; Laser detection system also has a lot of performance parameters to demarcate and to test, and these parameters comprise laser energy, laser pulse width, repetition frequency, laser beam divergence, laser far field distribution, system delay constant, the minimum detection sensitivity of system, receive field angle, optical axis registration.In these parameters that need accurately to demarcate and test; Except the parameter relevant with laser characteristics has unified method of testing; Other systematic parameter does not still have commercial device or the relevant apparatus of standard at present to its accurate demarcation, and this has brought puzzlement for demarcation of instrument detection performance.And same instrument be after the experience different conditions changes, and its performance parameter can change, the geometry factor of system particularly, and the variation of the geometry factor will directly have influence on the detectivity of system.This just requires to have the instrument of standard or equipment to test it, and in time calibrates situation of change.

Summary of the invention

The purpose of this invention is to provide a kind of twin shaft laser remote sensing instrument ground detection and calibration system, so that detection and the demarcation that can carry out systematization, quantification to the system performance and the instrument parameter of laser remote sensing instrument.

Another object of the present invention provides said system to the detectivity of main passive laser remote sensing instrument, the method that the far field beam quality distributes and the system geometries factor is carried out high-precision test and demarcation.

The technical scheme that the present invention adopted is that twin shaft laser remote sensing instrument ground detection and scaling system comprise analogue echo generator, two-dimentional mobile platform, large-aperture long-focus parallel light tube and beam quality analyser; One side of large-aperture long-focus parallel light tube is provided with beam splitter and prism of corner cube, and the opposite side of large-aperture long-focus parallel light tube is provided with total reflective mirror; The analogue echo generator is made up of photoelectric commutator, chronotron, optical fiber output laser, optical fiber and automatically controlled fibre optic attenuator; Photoelectric commutator and chronotron are between beam splitter and optical fiber output laser, and beam splitter is used for the pulse laser that is sent by the measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator; Photoelectric commutator is used for converting the pulse laser by the beam splitter reflection into electric signal; Chronotron is used for the time-delay of electric signal; Optical fiber output laser is used for triggered back output pulse laser by the electric signal after the time-delay; Optical fiber output laser is connected with an end of optical fiber; The other end of optical fiber is positioned at the opposite side of large-aperture long-focus parallel light tube; The port of the optical fiber other end is positioned on the focal plane of large-aperture long-focus parallel light tube, and is fixed on the two-dimentional mobile platform; Automatically controlled fibre optic attenuator is arranged on the optical fiber; The photosurface of beam quality analyser is placed on the large-aperture long-focus parallel light tube by on the focal plane of total reflective mirror reflection.

Another technical scheme that the present invention adopted does, utilizes above-mentioned twin shaft laser remote sensing instrument ground detection and scaling system to obtain the method for measured laser remote sensing instrument detectivity, comprises following operation steps:

Step 1: the measured laser remote sensing instrument sends pulse laser, and pulse laser is divided into two parts through beam splitter;

Step 2: wherein a part of pulse laser gets into total reflective mirror through large-aperture long-focus parallel light tube refraction back; Go on the beam quality analyser photosurface by total reflective mirror reflection is laggard; Form the emission laser facula, the far field beam quality that this emission laser facula of beam quality analyser collection obtains the measured laser remote sensing instrument distributes;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator of beam splitter; Trigger optical fiber output laser through after the time-delay of chronotron again; Pulse laser after optical fiber output laser is decayed by the automatically controlled fibre optic attenuator of other end output process of optical fiber through optical fiber; Pulse laser becomes directional light through the large-aperture long-focus parallel light tube; Wherein a part of directional light is through after 180 ° of reflections of prism of corner cube again after the reflection of the transmission through the large-aperture long-focus parallel light tube and total reflective mirror on the photosurface of directive beam quality analyser, formation analogue echo hot spot; And another part directional light gets into the measured laser remote sensing instrument and provides the output signal as remote analogue echo;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through the beam quality analyser; The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot on the beam quality analyser, overlap, realize that the measured laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the light path of treating measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system is to after connecting; Adjust the attenuation multiple of automatically controlled fibre optic attenuator; Make the output signal of measured laser remote sensing instrument reach detection limit; Utilize energy meter detection fiber output laser output energy value, and obtain the minimum detectable energy values P of laser remote sensing instrument according to automatically controlled fibre optic attenuator attenuation multiple value _Rmin, according to formula (1), obtain the detectivity of measured laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\τ}}_0{\mathrm{\τ}}^2{A}_r\mathrm{\σ}}{{\mathrm{\π}}^2{\mathrm{\θ}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In the formula, R _MaxBe that the observable maximum distance of laser remote sensing instrument is a detectivity, K distributes P by the beam quality that the beam quality analyser records _tBe the optical fiber output laser output power, τ ₀Be optical system efficiency, the τ Laser Atmospheric transmitance that is the measured laser remote sensing instrument on the target range, σ is the radar cross section of detected target, A _rBe receiving optics aperture area, θ _tBe the emission beam divergence angle, P _RminBeing the minimum detectable power of LDMS, also is system's detection sensitivity.

The technical scheme that the present invention also adopts does, utilizes above-mentioned twin shaft laser remote sensing instrument ground detection and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, comprises following operation steps:

Step 1: the measured laser remote sensing instrument sends pulse laser, and pulse laser is divided into two parts through beam splitter;

Step 2: wherein a part of pulse laser gets into total reflective mirror through large-aperture long-focus parallel light tube refraction back; Go on the beam quality analyser photosurface by total reflective mirror reflection is laggard; Form the emission laser facula, the far field beam quality that this emission laser facula of beam quality analyser collection obtains the measured laser remote sensing instrument distributes;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator of beam splitter; Trigger optical fiber output laser through after the time-delay of chronotron again; Pulse laser after optical fiber output laser is decayed by the automatically controlled fibre optic attenuator of other end output process of optical fiber through optical fiber; Pulse laser becomes directional light through the large-aperture long-focus parallel light tube; Wherein a part of directional light is through after 180 ° of reflections of prism of corner cube again after the reflection of the transmission through the large-aperture long-focus parallel light tube and total reflective mirror on the photosurface of directive beam quality analyser, formation analogue echo hot spot; And another part directional light gets into the measured laser remote sensing instrument and provides the output signal as remote analogue echo;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through the beam quality analyser; The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot on the beam quality analyser, overlap, realize that the laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the position of optical fiber other end end face when utilizing two-dimentional mobile platform record measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to achieve a butt joint is recorded as (L ₀, 0); Move horizontally on long-focus heavy caliber parallel light tube focal plane through two-dimentional mobile platform control optical fiber other end end face; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _L, 0) and (L _R, 0); Vertically move on long-focus heavy caliber parallel light tube focal plane through two-dimentional mobile platform control optical fiber other end end face; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _U, 0) and (L _D, 0); Obtain the laser remote sensing instrument geometry factor according to formula (2), also claim overlap factor how much:

${\mathrm{\δ}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f}$ ${\mathrm{\δ}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In the formula, f is the focal length of large-aperture long-focus parallel light tube, δ ₁Be the laser remote sensing instrument to be tested geometry factor in the horizontal direction, δ ₂The geometry factor for laser remote sensing instrument in the vertical direction to be tested.

The invention has the beneficial effects as follows; The far field beam quality that can obtain the passive laser remote sensing instrument of tested master exactly distributes and detectivity; And can obtain the geometry factor of the passive laser remote sensing instrument of tested master exactly; Solving spaceborne instrument before and after the experiment of experience all temps, hot vacuum environment, the geometry factor changes and the difficult problem that can't accurately demarcate.

Description of drawings

Fig. 1 is the structure principle chart of laser remote sensing instrument ground detection of the present invention and calibration system.

Among the figure, 1. beam splitter, 2. photoelectric commutator, 3. chronotron; 4. optical fiber output laser, 5. optical fiber, 6. automatically controlled fibre optic attenuator, 7. two-dimentional mobile platform; 8. total reflective mirror, 9. large-aperture long-focus parallel light tube, 10. beam quality analyser, 11. prism of corner cubes; 12. collimating and beam expanding system, 13. pulsed lasers, 14. receiving telescopes, 15. signal processing circuits.

Embodiment

As shown in Figure 1, the present invention provides a kind of twin shaft laser remote sensing instrument ground detection and scaling system, comprises analogue echo generator, two-dimentional mobile platform 7, large-aperture long-focus parallel light tube 9 and beam quality analyser 10; One side of large-aperture long-focus parallel light tube 9 is provided with beam splitter 1 and prism of corner cube 11, and the opposite side of large-aperture long-focus parallel light tube 9 is provided with total reflective mirror 8; The analogue echo generator is made up of photoelectric commutator 2, chronotron 3, optical fiber output laser 4, optical fiber 5 and automatically controlled fibre optic attenuator 6; Photoelectric commutator 2 and chronotron 3 are between beam splitter 1 and optical fiber output laser 4, and beam splitter 1 is used for the pulse laser that is sent by the measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator 2; Photoelectric commutator 2 is used for converting the pulse laser by beam splitter 1 reflection into electric signal; Chronotron 3 is used for the time-delay of electric signal; Optical fiber output laser 4 is used for triggered back output pulse laser by the electric signal after the time-delay; Optical fiber output laser 4 is connected with an end of optical fiber 5; The other end of optical fiber 5 is positioned at the opposite side of large-aperture long-focus parallel light tube 9; The port of optical fiber 5 other ends is positioned on the focal plane of large-aperture long-focus parallel light tube 9, and is fixed on the two-dimentional mobile platform 7; Automatically controlled fibre optic attenuator 6 is arranged on the optical fiber 5; The photosurface of beam quality analyser 10 is placed on large-aperture long-focus parallel light tube 9 by on the focal plane of total reflective mirror 8 reflections.

In the said system, the output wavelength of optical fiber output laser 4 is 1064nm, and pulsed frequency is adjustable at 1hz～1000hz; Optical fiber 5 is single-mode fiber, and core diameter is 9um; It is the desk-top attenuator of SUN-FVA-T that automatically controlled fibre optic attenuator 6 adopts model; Large-aperture long-focus parallel light tube 9 adopts the transmission-type system; Focal length is 4 meters; Bore is 500mm; Adopt large-aperture long-focus parallel light tube 9 to produce bigbore parallel beam, the sensing of this parallel beam and energy can accurately be controlled and demarcate, this heavy caliber light beam in order to simulation by the echo beam of reflection such as atmosphere, object or scattering generation; Utilize this echo beam to carry out analog detection, result of detection is analyzed and calculated just can obtain the omnibearing performance parameter index of laser remote sensing instrument the laser remote sensing instrument; Prism of corner cube 11 act as analogue echo light beam 180 degree reflected back large-aperture long-focus parallel light tubes 9; Beam quality analyser 10 adopts the Beammaster knife edge type beam analysis appearance of relevant company.

Wherein, the measured laser remote sensing instrument comprises pulsed laser 13, collimating and beam expanding system 12, receiving telescope 14 and signal processing circuit 15.

Utilize twin shaft laser remote sensing instrument ground detection provided by the invention and scaling system to obtain the method for measured laser remote sensing instrument detectivity, comprise following operation steps:

Step 1: the pulsed laser 13 of measured laser remote sensing instrument sends pulse laser, pulse laser by collimating and beam expanding system 12 collimator and extenders after, be divided into two parts through beam splitter 1;

Step 2: wherein a part of pulse laser gets into total reflective mirror 8 through large-aperture long-focus parallel light tube 9 refraction backs; Go on beam quality analyser 10 photosurfaces by total reflective mirror 8 reflection is laggard; Form the emission laser facula, beam quality analyser 10 is gathered the far field beam quality distribution that this emission laser facula obtains the measured laser remote sensing instrument;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator 2 of beam splitter 1; Again through triggering optical fiber output laser 4 after the time-delay of chronotron 3; Pulse laser after optical fiber output laser 4 is decayed by the automatically controlled fibre optic attenuator 6 of other end output process of optical fiber 5 through optical fiber 5; Pulse laser becomes directional light through large-aperture long-focus parallel light tube 9; Wherein a part of directional light is through after 180 ° of reflections of prism of corner cube 11 again after the reflection of the transmission through large-aperture long-focus parallel light tube 9 and total reflective mirror 8 on the photosurface of directive beam quality analyser 10, formation analogue echo hot spot; And the remote analogue echo of another part directional light conduct gets into the measured laser remote sensing instrument by receiving telescope 14 receptions, through also providing the output signal after signal processing circuit 15 processing;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through beam quality analyser 10; The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot on beam quality analyser 10, overlap, realize that the measured laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the light path of treating measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system is to after connecting; Adjust the attenuation multiple of automatically controlled fibre optic attenuator 6; Make the output signal of measured laser remote sensing instrument reach detection limit; Utilize energy meter detection fiber output laser 4 output energy values, and obtain the minimum detectable energy values P of laser remote sensing instrument according to automatically controlled fibre optic attenuator 6 attenuation multiple values _Rmin, according to formula 1, obtain the detectivity of measured laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\τ}}_0{\mathrm{\τ}}^2{A}_r\mathrm{\σ}}{{\mathrm{\π}}^2{\mathrm{\θ}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In the formula, R _MaxBe that the observable maximum distance of laser remote sensing instrument is a detectivity, K distributes P by the beam quality that beam quality analyser 10 records _tBe optical fiber output laser 4 output powers, τ ₀Be optical system efficiency, the τ Laser Atmospheric transmitance that is the measured laser remote sensing instrument on the target range, σ is the radar cross section of detected target, A _rBe receiving optics aperture area, θ _tBe the emission beam divergence angle, P _RminBeing the minimum detectable power of LDMS, also is system's detection sensitivity.

Utilize twin shaft laser remote sensing instrument ground detection provided by the invention and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, comprise following operation steps:

Step 1: the pulsed laser 13 of measured laser remote sensing instrument sends pulse laser, pulse laser by collimating and beam expanding system 12 collimator and extenders after, be divided into two parts through beam splitter 1;

Step 2: wherein a part of pulse laser gets into total reflective mirror 8 through large-aperture long-focus parallel light tube 9 refraction backs; Go on beam quality analyser 10 photosurfaces by total reflective mirror 8 reflection is laggard; Form the emission laser facula, beam quality analyser 10 is gathered the far field beam quality distribution that this emission laser facula obtains the measured laser remote sensing instrument;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator 2 of beam splitter 1; Again through triggering optical fiber output laser 4 after the time-delay of chronotron 3; Pulse laser after optical fiber output laser 4 is decayed by the automatically controlled fibre optic attenuator 6 of other end output process of optical fiber 5 through optical fiber 5; Pulse laser becomes directional light through large-aperture long-focus parallel light tube 9; Wherein a part of directional light is through after 180 ° of reflections of prism of corner cube 11 again after the reflection of the transmission through large-aperture long-focus parallel light tube 9 and total reflective mirror 8 on the photosurface of directive beam quality analyser 10, formation analogue echo hot spot; And the remote analogue echo of another part directional light conduct gets into the measured laser remote sensing instrument by receiving telescope 14 receptions, through also providing the output signal after signal processing circuit 15 processing;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through beam quality analyser 10; The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot on beam quality analyser 10, overlap, realize that the laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection;

Step 5: the position of optical fiber 5 other end end faces when utilizing two-dimentional mobile platform 7 record measured laser remote sensing instruments and laser remote sensing instrument ground detection and scaling system to achieve a butt joint is recorded as (L ₀, 0); Move horizontally on long-focus heavy caliber parallel light tube 9 focal planes through two-dimentional mobile platform 7 control optical fiber 5 other end end faces; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform 7 when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform 7 is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _L, 0) and (L _R, 0); Vertically move on long-focus heavy caliber parallel light tube 9 focal planes through two-dimentional mobile platform 7 control optical fiber 5 other end end faces; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform 7 when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform 7 is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _U, 0) and (L _D, 0); Obtain the measured laser remote sensing instrument geometry factor according to formula (2), also claim overlap factor how much:

${\mathrm{\δ}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f}$ ${\mathrm{\δ}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In the formula (2), f is the focal length of large-aperture long-focus parallel light tube 9, δ ₁Be the laser remote sensing instrument to be tested geometry factor in the horizontal direction, δ ₂The geometry factor for laser remote sensing instrument in the vertical direction to be tested.

The present invention adopts analogue echo generator and large-aperture long-focus parallel light tube 9 to produce to have that the orientation can accurately be controlled and demarcation, energy can accurately be regulated, bigbore remote analogue echo.The orientation of this analogue echo can and be demarcated by two-dimentional mobile platform 7 accurate controls, and the energy of this analogue echo is by automatically controlled fibre optic attenuator 6 controls.Utilize the actual detection state that this remote analogue echo can the simulated laser radar; The far field beam quality that can obtain the measured laser remote sensing instrument exactly distributes and detectivity; And can obtain the geometry factor of measured laser remote sensing instrument exactly; Solving spaceborne instrument before and after the experiment of experience all temps, hot vacuum environment, the geometry factor changes and the difficult problem that can't accurately demarcate.Utilize laser remote sensing instrument ground detection of the present invention and scaling system that the measured laser radar is surveyed, the detectivity that draws the measured laser radar is 18.9km.The present invention is to calibration uncertainty＜5% of detectivity, to the calibration uncertainty＜20urad of the geometry factor.

Claims (3)

1. twin shaft laser remote sensing instrument ground detection and scaling system is characterized in that: comprise analogue echo generator, two-dimentional mobile platform (7), large-aperture long-focus parallel light tube (9) and beam quality analyser (10); One side of large-aperture long-focus parallel light tube (9) is provided with beam splitter (1) and prism of corner cube (11), and the opposite side of large-aperture long-focus parallel light tube (9) is provided with total reflective mirror (8); Said analogue echo generator is made up of photoelectric commutator (2), chronotron (3), optical fiber output laser (4), optical fiber (5) and automatically controlled fibre optic attenuator (6); Photoelectric commutator (2) and chronotron (3) are positioned between beam splitter (1) and the optical fiber output laser (4); Beam splitter (1) is used for the pulse laser that is sent by the measured laser remote sensing instrument is divided into two parts, and wherein a part of pulse laser reflects to photoelectric commutator (2); Photoelectric commutator (2) is used for converting the pulse laser by beam splitter (1) reflection into electric signal; Chronotron (3) is used for the time-delay of electric signal; Optical fiber output laser (4) is used for triggered back output pulse laser by the electric signal after the time-delay; Optical fiber output laser (4) is connected with an end of optical fiber (5); The other end of optical fiber (5) is positioned at the opposite side of large-aperture long-focus parallel light tube (9); The port of optical fiber (5) other end is positioned on the focal plane of large-aperture long-focus parallel light tube (9), and is fixed on the two-dimentional mobile platform (7); Automatically controlled fibre optic attenuator (6) is arranged on the optical fiber (5); The photosurface of beam quality analyser (10) is placed on large-aperture long-focus parallel light tube (9) by on the focal plane of total reflective mirror (8) reflection.

2. utilize the described twin shaft laser remote sensing of claim 1 instrument ground detection and scaling system to obtain the method for measured laser remote sensing instrument detectivity, it is characterized in that, comprise following operation steps:

Step 1: the measured laser remote sensing instrument sends pulse laser, and pulse laser is divided into two parts through beam splitter (1);

Step 2: wherein a part of pulse laser gets into total reflective mirror (8) through large-aperture long-focus parallel light tube (9) refraction back; Go on beam quality analyser (10) photosurface by total reflective mirror (8) reflection is laggard; Form the emission laser facula, beam quality analyser (10) is gathered the far field beam quality distribution that this emission laser facula obtains the measured laser remote sensing instrument;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator (2) of beam splitter (1); Trigger optical fiber output laser (4) after passing through the time-delay of chronotron (3) again; Pulse laser after optical fiber output laser (4) is decayed by the other end output automatically controlled fibre optic attenuator of process (6) of optical fiber (5) through optical fiber (5); Pulse laser becomes directional light through large-aperture long-focus parallel light tube (9); Wherein a part of directional light through 180 ° of reflections of prism of corner cube (11) after again after the reflection of the transmission through large-aperture long-focus parallel light tube (9) and total reflective mirror (8) on the photosurface of directive beam quality analyser (10), formation analogue echo hot spot; And another part directional light gets into the measured laser remote sensing instrument and provides the output signal as remote analogue echo;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through beam quality analyser (10); The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot go up and overlap, realize that the measured laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection at beam quality analyser (10);

Step 5: the light path of treating measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system is to after connecting; Adjust the attenuation multiple of automatically controlled fibre optic attenuator (6); Make the output signal of measured laser remote sensing instrument reach detection limit; Utilize energy meter detection fiber output laser (4) output energy value, and obtain the minimum detectable energy values P of laser remote sensing instrument according to automatically controlled fibre optic attenuator (6) attenuation multiple value _Rmin, according to formula (1), obtain the detectivity of measured laser remote sensing instrument:

$R_{\max }={\left(\frac{{\mathrm{KP}}_t{\mathrm{\τ}}_0{\mathrm{\τ}}^2{A}_r\mathrm{\σ}}{{\mathrm{\π}}^2{\mathrm{\θ}}_t^2{P}_{r\min }}\right)}^{\frac{1}{4}}---\left(1\right)$

In the formula, R _MaxBe that the observable maximum distance of laser remote sensing instrument is a detectivity, K distributes P by the beam quality that beam quality analyser (10) records _tBe optical fiber output laser (4) output power, τ ₀Be optical system efficiency, the τ Laser Atmospheric transmitance that is the measured laser remote sensing instrument on the target range, σ is the radar cross section of detected target, A _rBe receiving optics aperture area, θ _tBe the emission beam divergence angle, P _RminBeing the minimum detectable power of LDMS, also is system's detection sensitivity.

3. utilize the described twin shaft laser remote sensing of claim 1 instrument ground detection and scaling system to obtain the method for the measured laser remote sensing instrument geometry factor, it is characterized in that, comprise following operation steps:

Step 1: the measured laser remote sensing instrument sends pulse laser, and pulse laser is divided into two parts through beam splitter (1);

Step 2: wherein a part of pulse laser gets into total reflective mirror (8) through large-aperture long-focus parallel light tube (9) refraction back; Go on beam quality analyser (10) photosurface by total reflective mirror (8) reflection is laggard; Form the emission laser facula, beam quality analyser (10) is gathered the far field beam quality distribution that this emission laser facula obtains the measured laser remote sensing instrument;

Step 3: another part pulse laser converts electric signal into through the reflection entering photoelectric commutator (2) of beam splitter (1); Trigger optical fiber output laser (4) after passing through the time-delay of chronotron (3) again; Pulse laser after optical fiber output laser (4) is decayed by the other end output automatically controlled fibre optic attenuator of process (6) of optical fiber (5) through optical fiber (5); Pulse laser becomes directional light through large-aperture long-focus parallel light tube (9); Wherein a part of directional light through 180 ° of reflections of prism of corner cube (11) after again after the reflection of the transmission through large-aperture long-focus parallel light tube (9) and total reflective mirror (8) on the photosurface of directive beam quality analyser (10), formation analogue echo hot spot; And another part directional light gets into the measured laser remote sensing instrument and provides the output signal as remote analogue echo;

Step 4: the position of relatively launching laser facula and analogue echo hot spot through beam quality analyser (10); The relative position of adjustment measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system; Make emission laser facula and analogue echo hot spot go up and overlap, realize that the laser remote sensing instrument docks with the light path of scaling system with laser remote sensing instrument ground detection at beam quality analyser (10);

Step 5: the position of optical fiber (5) other end end face when utilizing two-dimentional mobile platform (7) record measured laser remote sensing instrument and laser remote sensing instrument ground detection and scaling system to achieve a butt joint is recorded as (L ₀, 0); Move horizontally on long-focus heavy caliber parallel light tube (9) focal plane through two-dimentional mobile platform (7) control optical fiber (5) other end end face; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform (7) when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform (7) is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _L, 0) and (L _R, 0); Vertically move on long-focus heavy caliber parallel light tube (9) focal plane through two-dimentional mobile platform (7) control optical fiber (5) other end end face; Monitor measured laser remote sensing instrument output RST simultaneously; The position of two dimension mobile platform (7) when recording laser remote sensing instrument output signal becomes critical point, the shift position of two-dimentional mobile platform (7) is with respect to (L ₀, 0) and its two-dimentional shift position is designated as (L _U, 0) and (L _D, 0); Obtain the laser remote sensing instrument geometry factor according to formula (2), also claim overlap factor how much:

${\mathrm{\δ}}_1=\frac{L_L+L_R}{2f}-\frac{L_0}{f}$ ${\mathrm{\δ}}_2=\frac{L_U+L_D}{2f}-\frac{L_0}{f}---\left(2\right)$

In the formula, f is the focal length of large-aperture long-focus parallel light tube (9), δ ₁Be the laser remote sensing instrument to be tested geometry factor in the horizontal direction, δ ₂The geometry factor for laser remote sensing instrument in the vertical direction to be tested.

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