Dr. Mikhail Belenkii Profile

Dr. Mikhail Belenkii

Senior Supervisory Scientist at Trex Enterprises Corp

SPIE Involvement:

Conference Program Committee | Author

Publications (42)

PROCEEDINGS ARTICLE | May 5, 2017

Head-worn display for control of unmanned vehicles

Proc. SPIE. 10195, Unmanned Systems Technology XIX

KEYWORDS: Eye, Military display technology, Waveguides, Visualization, Cameras, Interfaces, Robots, Head-mounted displays, Unmanned vehicles, Vehicle control

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PROCEEDINGS ARTICLE | August 24, 2010

Portable daytime differential image motion sensor for atmospheric turbulence characterization

Proc. SPIE. 7814, Free-Space Laser Communications X

KEYWORDS: Signal to noise ratio, Short wave infrared radiation, Telescopes, Stars, Cameras, Sensors, Error analysis, Image sensors, Software development, Infrared telescopes

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PROCEEDINGS ARTICLE | September 28, 2007

Numerical analysis of hybrid adaptive optics system for correcting beacon anisoplanatism and thermal blooming

Proc. SPIE. 6711, Advanced Wavefront Control: Methods, Devices, and Applications V

KEYWORDS: Detection and tracking algorithms, Wavefront sensors, Wavefronts, Adaptive optics, Distortion, Linear filtering, Numerical analysis, Turbulence, Thermal blooming, Beam controllers

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PROCEEDINGS ARTICLE | September 27, 2007

Wavefront-based stochastic parallel gradient descent beam control

Proc. SPIE. 6711, Advanced Wavefront Control: Methods, Devices, and Applications V

KEYWORDS: Diffraction, Detection and tracking algorithms, Wavefront sensors, Wavefronts, Adaptive optics, Control systems, Turbulence, Algorithm development, Stochastic processes, Beam controllers

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PROCEEDINGS ARTICLE | September 25, 2007

Laboratory demonstration of wavefront-based stochastic parallel gradient descent adaptive optics system

Proc. SPIE. 6708, Atmospheric Optics: Models, Measurements, and Target-in-the-Loop Propagation

KEYWORDS: Beam splitters, Cameras, Adaptive optics, Control systems, Wave propagation, Turbulence, Aluminum, Dynamical systems, Thermal blooming, Beam controllers

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A laboratory demonstration of two novel tactical beam control methods for correcting the effects of strong turbulence including Beacon Anisoplanatism, and the combined effects of Beacon Anisoplanatism and Thermal Blooming, respectively, were performed in SAIC's Tactical Beam Control Test-Bed. Both systems were tested with ratio of aperture diameter to Fried parameter, D/r₀, of up to 7, and ratio of beam spot size at the target to isoplanatic angle, θ_B/θ_o, of up to 10. The first method was implemented in a Wavefront-based Stochastic Parallel Gradient Decent (WSPGD) adaptive optics (AO) system, which uses an off-axis wavefront sensor (WFS) to provide feedback for a multi-dithering beam control algorithm. The second method was implemented in a Hybrid WSPGD AO system, which incorporates the WSPGD AO system with a conventional Phase Conjugate (PC) AO system. The Hybrid system uses an on-axis WFS to generate initial deformable mirror commands and an off-axis WFS to generate additional commands that account for the high frequency phase components removed from the wavefront of a laser return by Beacon Anisoplanatism. We developed a low speed PC-based WSPGD controller, implemented designs of the WSPGD and Hybrid WSPGD AO systems in SAIC's Test-Bed, and tested both AO systems in static and dynamic turbulence over a wide range of turbulence conditions. A target-plane tracker was used to stabilize the line-of-sight in the AO corrected beam. Test results show that the WSPGD AO system efficiently compensates the effects of Beacon Anisoplanatism for both static and dynamic turbulence, providing a mean performance gain of 1.8 averaged over multiple turbulent realizations. We also found in testing that the Hybrid WSPGD system efficiently compensates for Beacon Anisoplanatism in the presence of Thermal Blooming - providing improved compensation for both Thermal Blooming and turbulence. In the presence of strong Beacon Anisoplanatism with θ_B/θ_o of up to 10, the maximum performance gain is 4.9 and the mean performance gain for multiple turbulence realizations is 2.1.

PROCEEDINGS ARTICLE | September 25, 2007

Turbulence inner scale sensor for arbitrary atmospheric paths

Proc. SPIE. 6709, Free-Space Laser Communications VII

KEYWORDS: Signal to noise ratio, Point spread functions, Telescopes, Stars, Sensors, Turbulence, Scintillation, Atmospheric propagation, Atmospheric sensing, Atmospheric optics

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PROCEEDINGS ARTICLE | September 1, 2006

Experimental study of spatial structure of turbulence at Maui Space Surveillance Site (MSSS)

Proc. SPIE. 6304, Free-Space Laser Communications VI

KEYWORDS: Point spread functions, Telescopes, Stars, Cameras, Wavefronts, Surveillance, Data acquisition, Space telescopes, Turbulence, Anisotropy

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We investigated the spatial structure of atmospheric turbulence at Maui Space Surveillance Site (MSSS) using a 3.6 m telescope and a spatial filtering receiver. This receiver simultaneously records four star images on one camera frame. The star images are formed through pupil masks representing aperture diameters of 0.1 m, 0.5m, 1.5 m, and 3.6 m. We determined the camera orientation for each data set by moving the telescope at a given angle in azimuth and elevation. We calculated the horizontal and vertical components of the image centroid and evaluated the statistics of the horizontal and vertical wavefront tilt as a function of the aperture diameter and seeing conditions. We found several evidences of anisotropy of turbulence at MSSS. On four nights we observed that the variance of on-axis horizontal tilt exceeded the variance of the vertical tilt by a factor of 1.3-3.3. We believe that this is due to anisotropy of large-scale turbulence, where the horizontal scale of the turbulent inhomogeneities exceeds their vertical scale. The estimates of the horizontal and vertical turbulence outer scale confirmed this conclusion. In addition, in several data sets the horizontal image spot diameter of the long-exposure star image exceeded the vertical image spot diameter. We also found that large apertures are more likely to have higher anisotropy coefficient values than small apertures. This is because the contribution of small-scale isotropic turbulence to the image centroid reduces with increasing telescope diameter. In the case of isotropic turbulence, the power spectral densities (PSDs) of wavefront tilt are consistent with theoretical models. The telescope vibration modes were observed at 20 Hz. In the case of anisotropic turbulence, the PSDs of the horizontal tilt component have lower slope in the high frequency range, and difference between PSDs for large and small apertures is reduced. The anisotropy of turbulence and atmospheric tilt may affect the design and performance analysis of both active and passive optical systems.

PROCEEDINGS ARTICLE | September 13, 2005

Energy flux conservation law and scintillation-free laser communication system demonstration

Proc. SPIE. 5892, Free-Space Laser Communications V

KEYWORDS: Signal to noise ratio, Transmitters, Retroreflectors, Modulation, Receivers, Telecommunications, Turbulence, Scintillation, Laser communications, Laser systems engineering

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PROCEEDINGS ARTICLE | August 23, 2005

Tracking in clutter and effects of thermal blooming on HEL beams

Proc. SPIE. 5895, Target-in-the-Loop: Atmospheric Tracking, Imaging, and Compensation II

KEYWORDS: Detection and tracking algorithms, Cameras, Directed energy weapons, Thermal effects, Optical flow, Optical tracking, Motion models, Atmospheric propagation, Thermal blooming, Motion estimation

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PROCEEDINGS ARTICLE | October 25, 2004

Free-space laser communication model

Proc. SPIE. 5595, Active and Passive Optical Components for WDM Communications IV

KEYWORDS: Signal to noise ratio, Statistical analysis, Receivers, Turbulence, Scintillation, Atmospheric propagation, Performance modeling, Atmospheric modeling, Systems modeling, Visibility

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PROCEEDINGS ARTICLE | October 20, 2004

Target edge response

Proc. SPIE. 5550, Free-Space Laser Communications IV

KEYWORDS: Point spread functions, Visible radiation, Imaging systems, Cameras, Data acquisition, Image quality, Scintillation, Modulation transfer functions, Spatial resolution, Atmospheric optics

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PROCEEDINGS ARTICLE | September 8, 2004

Wavelength selection and propagation analysis for shipboard free electron laser

Proc. SPIE. 5413, Laser Systems Technology II

KEYWORDS: Scattering, Aerosols, Wave propagation, Turbulence, Atmospheric propagation, Free electron lasers, Atmospheric particles, Thermal blooming, Atmospheric modeling, Absorption

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PROCEEDINGS ARTICLE | January 27, 2004

Residual turbulent scintillation effect and impact of turbulence on the Fourier telescopy system

Proc. SPIE. 5160, Free-Space Laser Communication and Active Laser Illumination III

KEYWORDS: Spatial frequencies, Satellites, Free space, Laser beam propagation, Turbulence, Scintillation, Atmospheric propagation, Beam propagation method, Atmospheric scintillation, Visibility

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The e ffects o f a tmospheric turbulence o n the g round—to-space p ropagation p ath a nd P oisson sh ot n oise o n a n a ctive laser-based imaging system for high-resolution imaging of Geosynchronous (GEO) satellites are investigated using a wave-optics simulation code. The phase and scintillation statistics in tilt corrected and uncorrected beams are examined at the top ofthe atmosphere and at the satellite. The effects of intensity and phase variations in the illuminating beams on the fringe visibility and spatial frequency of the interference pattern formed by the illuminating beams at the satellite are investigated. The Fourier phase variance caused by Poisson shot noise and turbulence on the uplink path is evaluated. We found that tilt correction reduces the scintillation in the laser beam at the satellite. In the Fourier telescopy system the scintillation variance at the edge of the beam is reduced by a factor of up to 3 for a tilt corrected beam. Long-range propagation in free space reduces scintillation in the illuminating beam. The scintillation variance in the Fourier telescopy system on the optical axis at the satellite is reduced by 26% to 36 %, as compared to that at the top of the atmosphere. The latter is due to diffraction of the laser beam in free space and enhancement of the spatial coherence of the beam described by the Van Cittert-Zernike theorem. The intensity spatial correlation scale in the scintillation pattern exceeds the satellite dimensions. This leads to a so-called residual turbulent scintillation effect, when the scintillation in the illuminating beam modulates the total reflected energy flux. As a result, an arbitrarily large receiver on the ground cannot average the received signal variations. This degrades the Fourier telescopy system performance. Also intensity and phase variations in the illuminating beams degrade the interference pattern formed at the satellite. The turbulence effect on the fringe visibility is stronger at high spatial frequencies. Intensity variations in the illuminating beams degrade the fringe visibility the most. Poisson shot noise and scintillation on the uplink path strongly impacts the Fourier phase of the object. In the turbulent atmosphere the Fourier phase variance increases by a factor of 1 .5-3, as compared to that in free space. The increase of the phase variance is caused by a non-linear interaction between the two statistically independent noise sources. For the nominal signal level and number of averaged pulses the Fourier phase variance is less than 0.1, or ()L I20)2 . This suggests that the Fourier telescopy method is feasible.

PROCEEDINGS ARTICLE | January 27, 2004

Measurement of tilt anisoplanatism with discrete and extended sources

Proc. SPIE. 5160, Free-Space Laser Communication and Active Laser Illumination III

KEYWORDS: Visible radiation, Optical sensors, Statistical analysis, Imaging systems, Cameras, Sensors, Data acquisition, Turbulence, Projection systems, Scintillation

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A dual-band imaging system with variable aperture diameter was constructed and horizontal and vertical atmospheric tilt components were measured on a 1-km near-the-ground horizontal path using discrete and extended visible and JR sources. The spatial and temporal tilt statistics were estimated from the recorded data. Tilt structure function, which also characterizes v ariance of the p ointing error caused by anisoplanatism of t he track point to the aim point in the 1 aser projection system, for small angular separation decreases inverse proportionally to the aperture diameter D1 . The tilt structure function is insensitive to sensor vibration. For a point ahead angle of 0.45 mrad the daytime rms pointing enor caused by tilt anisoplanatism is 12 prad for D= 6 cm, and it is 5 prad for D= 40 cm. The tilt power spectral density agrees well with theory. Jt has the "-2/3" power slope, and the ratio of the two knee frequencies is equal to the inverse ratio of the aperture diameters. The tilt temporal conelation increases with the aperture diameter. The temporal conelation scale is 0.25 sec for D=6 cm and it is 1 sec for D= 40 cm. The C measurements made with discrete JR sources and an optical imager agree well with the measurements made with a scintillometer. The structure function for the lateral (Y) tilt exceeds that for the longitudinal (X) tilt, which is inconsistent with the theoretical prediction. We believe that heat-induced turbulence from the JR sources and a wind component parallel to the optical path degraded the measurements of the vertical tilt. Three mitigation techniques were considered including an increase of the aperture diameter, integration of the image edge over the edge angular extent, and averaging of multiple frames. A multi-frame averaging technique is known to be efficient for mitigation of the effects of turbulence induced scintillation and laser speckle. We found that by averaging multiple image frames one can mitigate the effects of tilt anisoplanatism as well. We also found that the edge response for a multi frame averaged image and a single frame image is the same. This allows us to conclude that a multi frame averaging technique for an extended object does not affect the system angular resolution.

PROCEEDINGS ARTICLE | August 21, 2003

Tracking through laser-induced clutter for air-to-ground directed energy system

Proc. SPIE. 5087, Laser Systems Technology

KEYWORDS: Mid-IR, Detection and tracking algorithms, Sensors, Synthetic aperture radar, Free space, Directed energy weapons, Turbulence, Thermal effects, Optical tracking, Thermal blooming

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PROCEEDINGS ARTICLE | August 21, 2003

Beacon anisoplanatism

Proc. SPIE. 5087, Laser Systems Technology

KEYWORDS: Transmitters, Speckle, Sensors, Free space, Adaptive optics, Wave propagation, Turbulence, Scintillation, Phase measurement, Atmospheric propagation

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PROCEEDINGS ARTICLE | December 9, 2002

Effect of turbulence on downlink and horizontal path on high-order coherence moments in Fourier telescopy system

Proc. SPIE. 4821, Free-Space Laser Communication and Laser Imaging II

KEYWORDS: Signal to noise ratio, Speckle, Satellites, Receivers, Free space, Turbulence, Scintillation, Phase measurement, Atmospheric turbulence, Visibility

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Fourier Telescopy is an active laser-based imaging method for high-resolution imaging of dim objects in Geosynchronous (GEO) orbit. The Geo Light Imaging National Testbed will be buit to demonstrate new powerful imaging capability. Several processes including laser speckle, atmospheric turbulence on the downlink and 1-km horizontal path, as well as Poisson shot noise can contribute to the measurement error of the Fourier phase of the object and thus degrade the reconstructed image. We investigated the impact of three processes including laser speckle, turbulence, and Poisson shot noise on the measurement error of the Fourier phase. We introduced the concept of power-in-the-bucket receiver and applied this concept to the receiver in the Fourier telescopy system. We found that the power-in-the-bucket receiver cancels the effects of turbulence on the horizontal path on the Fourier telescopy system. We evaluated variance of the real and imaginary parts of the triple product, as well as variance of the Fourier phase of the object by using a numercal simulation code. The twelfth moment of the optcal filed was calculated in the resenceof laser speckle, atmospheric turbulence, and Poisson shot noise. Simulation results confirmed that Fourier telescopy system is immune to the efects of turbulence on the horizontal path. It also showed that the effect of turbulence on the downlink path on the triple product is small. Laser speckle contributes strongly to the variations of the real part of the triple product and weakly to the imaginary part. Statistical properties of the triple product depend on the noise source. Poisson shot noise and laser speckle poduce the main contribution to the variance of the triple product and measurement error of the object Fourier pase. Phase variance reduces with increasing the number of heliostats, number of pulses, fringe visibility, and fringe signal-to-noise ratio. For 40 heliostat receivers, 100 averaged pulses, and all considered fringe SNRs and fringe visibilities the phase variance caused by Poisson noise, laser speckle, and turbulence on the downlink path is significantly less than 0.36, which corresponds to the phase measurement accuracy of 1/10 of the wave.

PROCEEDINGS ARTICLE | January 22, 2002

Enhanced backscatter and turbulence effects on pupil-plane speckle imaging system

Proc. SPIE. 4489, Free-Space Laser Communication and Laser Imaging

KEYWORDS: Backscatter, Imaging systems, Speckle, Argon, Satellites, Free space, Turbulence, Scintillation, Speckle imaging, Atmospheric propagation

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We investigate the effects of turbulence on pupil-plane speckle imaging system that has been proposed to provide high-resolution images of a low Earth orbit (LEO) satellite using laser illumination. We present a theory and numerical results for the normalized speckle covariance for one- dimensional object in the turbulent atmosphere and demonstrate that turbulence-induced anisoplanatism and scintillation degrades this characteristic. The effect of anisoplanatism is associated with the finite size of a satellite. Due to a finite satellite dimension, optical waves arrive at the receiver from different directions determined by the angular size of the satellite and sample different turbulence. The resulting phase difference degrades the normalized speckle covariance. This effect is similar to the degradation of the performance of adaptive optics system caused by turbulence-induced anisoplanatism when a reference beacon is separated from the target at some distance. Scintillation on the downlink path also degrades the normalized speckle covariance. It causes the dc- and ac- components of the speckle correlation to exceed their values in a free space when the separation between the observation points is smaller than the spatial correlation scale of the scintillation. At the same time, both components are decreased for large separations when scintillation is uncorrelated. This reduces the normalized speckle covariance and can degrade the performance of a pupil-plane speckle imaging system. The effect of scintillation on the dc- and ac-components of the speckle correlation is similar to the enhanced backscatter phenomenon, in which the average power of the laser return in the strictly backward direction in the turbulent atmosphere exceeds its value in free space. For a small object, the effect of scintillation on the speckle covariance predominates. The speckle statistics for the space-to-ground scenario differ from that for the horizontal path.

PROCEEDINGS ARTICLE | January 22, 2002

Coherence degradation of a speckle field and turbulence effects on Fourier telescopy imaging system

Proc. SPIE. 4489, Free-Space Laser Communication and Laser Imaging

KEYWORDS: Imaging systems, Spatial frequencies, Speckle, Satellites, Receivers, Free space, Satellite imaging, Turbulence, Spatial coherence, Polonium

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PROCEEDINGS ARTICLE | September 19, 2001

Experimental validation of the differential image motion lidar concept

Proc. SPIE. 4377, Laser Radar Technology and Applications VI

KEYWORDS: Scattering, LIDAR, Sensors, Laser scattering, Receivers, Turbulence, Image transmission, Scintillation, Analog electronics, Motion measurement

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PROCEEDINGS ARTICLE | September 18, 2001

Turbulence-induced edge image waviness: theory and experiment

Proc. SPIE. 4370, Targets and Backgrounds VII: Characterization and Representation

KEYWORDS: Infrared imaging, Astronomy, Data modeling, Imaging systems, Cameras, Image processing, Video, Turbulence, Analytical research, Spherical lenses

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PROCEEDINGS ARTICLE | September 27, 1999

Experimental validation of tilt measurement technique with a laser beacon

Proc. SPIE. 3762, Adaptive Optics Systems and Technology

KEYWORDS: Telescopes, Wavefront sensors, Wavefronts, Receivers, Adaptive optics, Turbulence, Charge-coupled devices, Laser guide stars, Motion measurement, Atmospheric sensing

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PROCEEDINGS ARTICLE | September 27, 1999

Preliminary experimental evidence of anisotropy of turbulence and the effect of non-Kolmogorov turbulence on wavefront tilt statistics

Proc. SPIE. 3762, Adaptive Optics Systems and Technology

KEYWORDS: Telescopes, Stars, Data modeling, Cameras, Wavefronts, Data acquisition, Wave propagation, Turbulence, Atmospheric modeling, Anisotropy

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PROCEEDINGS ARTICLE | July 19, 1999

Experimental evidence of the effects of non-Kolmogorov turbulence and anisotropy of turbulence

Proc. SPIE. 3749, 18th Congress of the International Commission for Optics

KEYWORDS: Telescopes, Optical filters, Optical design, Statistical analysis, Stars, Wavefronts, Adaptive optics, Domes, Turbulence, Anisotropy

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PROCEEDINGS ARTICLE | November 3, 1998

Mitigation of the turbulent degradation effects in a laser beam

Proc. SPIE. 3433, Propagation and Imaging through the Atmosphere II

KEYWORDS: Transmitters, Coherence (optics), Wavefront sensors, Wavefronts, Wavefront aberrations, Collimation, Turbulence, Scintillation, Spherical lenses, Atmospheric propagation

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PROCEEDINGS ARTICLE | October 17, 1997

Experimental study of the effect of non-Kolmogorov stratospheric turbulence on star image motion

Proc. SPIE. 3126, Adaptive Optics and Applications

KEYWORDS: Telescopes, Stars, Data modeling, Space telescopes, Turbulence, Scintillation, Motion models, Motion measurement, Atmospheric modeling, Anisotropy

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PROCEEDINGS ARTICLE | October 17, 1997

Measurements of tilt angular anisoplanatism

Proc. SPIE. 3126, Adaptive Optics and Applications

KEYWORDS: Telescopes, Stars, Data modeling, Imaging systems, Image resolution, Wavefronts, CCD cameras, Data processing, Turbulence, Motion measurement

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PROCEEDINGS ARTICLE | October 17, 1997

Multiple-aperture averaging technique for measuring full aperture tilt with a laser guide star

Proc. SPIE. 3126, Adaptive Optics and Applications

KEYWORDS: Telescopes, Error analysis, Receivers, Adaptive optics, Turbulence, Projection systems, Laser guide stars, Motion measurement, Plasma display panels, Sodium guide stars

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PROCEEDINGS ARTICLE | January 6, 1997

Tilt angular correlation and tilt sensing techniques with a laser guide star

Proc. SPIE. 2956, Optics in Atmospheric Propagation, Adaptive Systems, and Lidar Techniques for Remote Sensing

KEYWORDS: Transmitters, Telescopes, Mirrors, Scattering, Receivers, Turbulence, Image transmission, Sodium, Laser guide stars, Motion measurement

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PROCEEDINGS ARTICLE | October 14, 1996

Single-ended laser wind sensor

Proc. SPIE. 2828, Image Propagation through the Atmosphere

KEYWORDS: Telescopes, Fringe analysis, Sensors, Laser development, Receivers, Speckle pattern, Chlorine, Signal detection, Wind measurement, Prototyping

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PROCEEDINGS ARTICLE | October 14, 1996

Design of an optical remote sensing system for measuring refractive turbulence in the Antarctic boundary layer

Proc. SPIE. 2828, Image Propagation through the Atmosphere

KEYWORDS: Transmitters, Backscatter, LIDAR, Aerosols, Remote sensing, Receivers, Turbulence, Motion measurement, Pulsed laser operation, Atmospheric modeling

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PROCEEDINGS ARTICLE | October 14, 1996

Principle of equivalency of the phase difference and off-axis tilt sensing technique with a laser guide star

Proc. SPIE. 2828, Image Propagation through the Atmosphere

KEYWORDS: Telescopes, Stars, Error analysis, Receivers, Wave propagation, Collimation, Sodium, Laser guide stars, Motion measurement, Atmospheric propagation

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PROCEEDINGS ARTICLE | June 15, 1995

Prospects for laser remote sensing of Cn2

Proc. SPIE. 2471, Atmospheric Propagation and Remote Sensing IV

KEYWORDS: Atmospheric laser remote sensing, Backscatter, LIDAR, Remote sensing, Receivers, Distortion, Turbulence, Scintillation, Image enhancement, Atmospheric optics

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PROCEEDINGS ARTICLE | June 15, 1995

Full-aperture tilt measurement technique with a laser guide star

Proc. SPIE. 2471, Atmospheric Propagation and Remote Sensing IV

KEYWORDS: Transmitters, Telescopes, Stars, Scattering, Receivers, Adaptive optics, Wave propagation, Image transmission, Laser guide stars, Atmospheric optics

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PROCEEDINGS ARTICLE | June 15, 1995

Influence of stratospheric turbulence on infrared imaging

Proc. SPIE. 2471, Atmospheric Propagation and Remote Sensing IV

KEYWORDS: Infrared imaging, Stars, Coherence (optics), Data modeling, In situ metrology, Turbulence, Scintillation, Stratosphere, Troposphere, Atmospheric modeling

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PROCEEDINGS ARTICLE | June 15, 1995

Influence of the stratospheric turbulence on the adaptive optics systems performance

Proc. SPIE. 2471, Atmospheric Propagation and Remote Sensing IV

KEYWORDS: Telescopes, Stars, Data modeling, Wavefronts, Adaptive optics, Turbulence, Motion models, Motion measurement, Stratosphere, Atmospheric propagation

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PROCEEDINGS ARTICLE | June 29, 1994

New non-Doppler remote sensing technique for 3-D wind field mapping

Proc. SPIE. 2222, Atmospheric Propagation and Remote Sensing III

KEYWORDS: Photodetectors, Statistical analysis, Three dimensional sensing, LIDAR, Remote sensing, Signal processing, Wind energy, Correlation function

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PROCEEDINGS ARTICLE | June 29, 1994

Design considerations for a residual turbulent scintillation (RTS) lidar

Proc. SPIE. 2222, Atmospheric Propagation and Remote Sensing III

KEYWORDS: Transmitters, Imaging systems, LIDAR, Receivers, Profiling, Objectives, Scintillation, Gated imaging, Optical instrument design, Pulsed laser operation

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PROCEEDINGS ARTICLE | June 29, 1994

New perspective in the experimental study of atmospheric turbulence: a volume scanning crossed-path lidar technique

Proc. SPIE. 2222, Atmospheric Propagation and Remote Sensing III

KEYWORDS: Radar, Refractive index, LIDAR, Temporal resolution, Humidity, Spatial resolution, Atmospheric turbulence, Acoustics, Atmospheric optics

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PROCEEDINGS ARTICLE | June 29, 1994

Monostatic image distortion lidar technique for measuring intensity of atmospheric turbulence

Proc. SPIE. 2222, Atmospheric Propagation and Remote Sensing III

KEYWORDS: Refractive index, Astronomy, LIDAR, Remote sensing, Laser beam propagation, Adaptive optics, Distortion, Turbulence, Atmospheric turbulence, Atmospheric propagation

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PROCEEDINGS ARTICLE | May 31, 1994

Fundamental limitation in adaptive optics: how to eliminate it? A full-aperture tilt measurement technique with a laser guide star

Proc. SPIE. 2201, Adaptive Optics in Astronomy

KEYWORDS: Signal to noise ratio, Transmitters, Telescopes, Stars, Argon, Receivers, Adaptive optics, Laser guide stars, Wavefront distortions, Atmospheric propagation

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PROCEEDINGS ARTICLE | September 15, 1993

New remote sensing technique for lidar monitoring of atmospheric turbulence

Proc. SPIE. 1968, Atmospheric Propagation and Remote Sensing II

KEYWORDS: Atmospheric laser remote sensing, Backscatter, Scattering, LIDAR, Remote sensing, Laser scattering, Receivers, Turbulence, Atmospheric propagation, Atmospheric particles

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