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Showing 1 to 10 of 10 for “"Scintillation Index"”.
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The Scintillation Index In Moderate To Strong Turbulence For The Gaussian Beam Wave Along A Slant Path
Scintillation is one of the most common statistics in the literature of mathematical modeling of laser propagation through random media. One approach to estimating scintillation is through the Rytov approximation, which is limited to weak atmospheric turbulence. Recently, an improvement of the …
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Propagation of Gaussian Beams Through a Modified von Karman Phase Screen
… screen during Gaussian beam propagation on the scintillation index for a single beam and on the fringe visibility for the two transversely separated beams. We use the modified von Karman spectrum model to describe the phase screen statistics, utilizing the Fried parameter, inner scale and the …
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Measuring Optical Turbulence Parameters With A Three-aperture Receiver
… with three different receiving apertures. The scintillation index is found for each receiving aperture and recently developed theory for all regimes of optical turbulence is used to infer three atmospheric parameters, Cn2, l0, and L0. The transverse wind speed is also calculated from the …
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The Effectiveness Of Data Codes And Hardware Selection To Mitigate Scintillation Effects On Free Space Optical Data Transmission
… receiving devices, and compared the resultant scintillation index with the theoretical calculations.
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Forward scattering of a pulsed continuous wave signal through laminar and turbulent thermal plumes
… the plume moves from laminar to turbu lent, the scintillation index and the Fourier transform of the magnitude square response provide insight into the nature of the transition. Finally, from the turbulent response a model for the scattering function is developed.
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Simulation of High Frequency Waves Reflected From a Turbulent Ionosphere for Spread Spectrum Systems
… power spectrum, correlation function and scintillation index. For communication purposes, the pulse distortion is of major interest. The two-frequency mutual coherence function is computed to determine the statistical behavior of the received signal. The coherence bandwidth resulting from …
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The Wave Structure Function And Temporal Frequency Spread In Weak To Strong Optical Turbulence
… spectral model presented by Andrews et al. for scintillation index, wave structure function expressions have been derived that are valid in all turbulence conditions as evidenced by comparison to experimental data. Analytic wave structure function results are developed for plane, spherical, and …
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Simulating the use of channel reciprocity in laser communication system operations to improve quality of service through varying atmospheric conditions
… For example, the user may elect to sweep the scintillation index to see the impact that a variety of turbulence levels have on the bit error rate (BER). The user has the ability to sweep each variable and observe the performance. With this model, the user objectively compares optical …
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GNSS-based Hardware-in-the-loop Simulation of Spacecraft Formation Flight: An Incubator for Future Multi-scale Ionospheric Space Weather Studies
… total electron density (TEC) and GNSS scintillation index S4 are measured by the LEO GNSS receivers in simulated scenarios. Four stages of work were accomplished to (i) build the VTFFTB with a global ionospheric modeling capability, and (ii) apply the VTFFTB to incubate future …
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Keer electro-optic measurements in liquid dielectrics
… in the absence of high voltage, the optical scintillation index and image entropy exhibit substantial enhancement and reduction respectively, which are interpreted as temporal and spatial signatures of turbulence. Under low-frequency ac high voltages, spectral and correlation analyses also …