Results 271 to 280 of about 17,683 (311)

Coding for the Turbulent Atmospheric Optical Channel

IEEE Transactions on Communications, 1982
In the presence of atmospheric or aircraft boundary layer turbulence, an optical channel may need large amounts of link margin to combat fading and beam spreading. Channel coding can reduce the average transmitter power required for reliable communication.
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Atmospheric Turbulence in Optical Surveillance Systems

Applied Optics, 1967
The limitations imposed by atmospheric turbulence in the design of optical surveillance systems with slant optical paths are developed. Image blurring effects which determine scene contrast ratio are separated from spot dancing effects which determine signal-to-noise ratio. The relative position of each turbulent eddy with respect to scene and observer
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Nonlinear Optics and Turbulence

1992
Abstract : The ongoing and primary goal of the research is the pursuit of understanding of nonlinear processes in natural phenomena arising in optics and fluids. A considerable share of our attention is devoted to nonlinear optics, a relatively young subject, extremely rich in scientific and technological potential.
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Measurements of anisotropy in optical turbulence

2017 IEEE Aerospace Conference, 2017
A Hartmann Turbulence Sensor was employed along a 200 meter path over a grassy field to investigate turbulence anisotropy. This sensor was based on a 16″ telescope with a 32 × 32 subaperture array featuring 700 active subapertures and a camera operating as fast as 8000 frames/sec.
Jack E. McCrae, Santasri R. Bose-Pillai, Matthew G. Current, Kevin P. Lee, Steven T. Fiorino   +4 more
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From hexagons to optical turbulence

Conference Digest. 2000 International Quantum Electronics Conference (Cat. No.00TH8504), 2005
Summary form only given. The transition from regular static patterns observed in optical systems to spatio-temporal chaotic regimes is not yet well understood. We address this problem in a ring cavity filled with a nonlinear self-focusing Kerr medium pumped by an external field.
SANTAGIUSTINA, MARCO, GOMILA D, COLET P, SAN MIGUEL M, HOYUELOS M.   +4 more
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Fiber-optic atmospheric turbulence sensor

Optics Letters, 1995
A novel dual-air-gap fiber-optic Mach - Zehnder interferometer is proposed for the direct measurement of the atmospheric optical turbulence structure constant C(n)(2). The shot-noise-limited minimum detectable structure constant is estimated to be 4.5 x 10(-20) m(-2/3), which is more than 2 orders of magnitude below a typical value of 10(-17) m(-2/3 ...
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Optical Topologies in Turbulence

Optica Imaging Congress 2024 (3D, AOMS, COSI, ISA, pcAOP)
Light can be imbued with a topology, but is the topological invariant immune to turbulence? Here I outline how to find invariants in light's degrees of freedom for noise-free communication through turbulence.
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Optical Turbulence in the Atmosphere

2009
Overview: In this chapter we present a brief treatment of atmospheric turbulence as it pertains to velocity fluctuations (classical turbulence), temperature fluctuations, and index of refraction fluctuations, the latter often referred to as optical turbulence.
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Many-parameter routes to optical turbulence

Physical Review A, 1986
The output of an externally pumped passive nonlinear-optical ring resonator is known to exhibit chaotic dynamics under variation of one or more external control parameters. The dynamics of the internal transverse laser beam profile is described, in the good-cavity limit, by an infinite-dimensional discrete-time map in function space.
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Underwater turbulence, its effects on optical wireless communication and imaging: A review

Optics and Laser Technology, 2022
Yahya Baykal, Yalcin Ata, Muhsin Caner Gökçe   +2 more
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