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Showing 1 to 7 of 7 for “"optical turbulence"”.
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Measuring Optical Turbulence Parameters With A Three-aperture Receiver
… several atmospheric parameters related to turbulence. Techniques used by two different scintillometers based on weak turbulence theory are discussed along with a method to estimate the inner scale developed by Hill. The theory and minimization algorithm used to infer the atmospheric …
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The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence
… spectrum, and the temporal frequency spectrum of optical signals propagating through a random medium, specifically the Earth’s atmosphere. The results are believed to be valid for all optical turbulence conditions. These expressions are developed using the Rytov approximation method. Generally, …
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Fade Statistics For A Lasercom System And The Joint Pdf Of A Gamma-gamma Distributed Irradiance And Its Time Derivative
… operating in the atmosphere is reduced by optical turbulence, which causes irradiance fluctuations in the received signal. The result is a randomly fading signal. Fade statistics for lasercom systems are determined from the probability density function (PDF) of the irradiance fluctuations. …
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High-Dimensional Quantum Information: From Sensing to Underwater Quantum Communication
… Laguerre-Gaussian (LG) and vector vortex optical modes in underwater quantum communication channels. Making use of these high-dimensional states in quantum communication provides certain advantages including increased security and increased information capacity. We investigate underwater …
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Profiling the turbulent atmosphere and novel correction techniques for imaging and photometry in astronomy
… astronomy. The phase aberration induced by the turbulence broaden the point spread function (PSF) and limits the resolution for imaging. If there is strong turbulence high in the atmosphere then these phase aberration propagate and develop into intensity fluctuations (scintillation). This thesis …
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The Scintillation Index In Moderate To Strong Turbulence For The Gaussian Beam Wave Along A Slant Path
… which is limited to weak atmospheric turbulence. Recently, an improvement of the Rytov approximation was developed employing a linear filter function technique. This modifies the Rytov approximation and extends the validity into the moderate to strong regime. In this work, an …
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Astronomical seeing conditions as determined by turbulence modelling and optical measurement
… to be hosted on-site. This technique requires optical (or so-called astronomical) seeing conditions, which allow for the propagation of a laser beam through the atmosphere without excessive beam degradation. The seeing must be at ~ 1 arc second resolution level for LLR to deliver usable ranging …