Results 291 to 300 of about 7,448,970 (353)

An index of phase distortion

International Journal of Circuit Theory and Applications, 1986
AbstractMeasures exclusively reflecting phase distortion are examined and a new phase distortion ‘index’ is proposed. This index, based on the mean‐squared degradation in the impulse response of a filter, is shown to be equivalent to a phase distortion ‘spot‐measure’ using the variation in the peak value of the impulse response, due to phase distortion,
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Phase Distortion Study (Phase B)

1977
Abstract : This is the Final Report of a 6 month study of duobinary digital data transmission over the DSCS. Analysis and computer simulations were developed for evaluating the degradation for duobinary SQPSK in the FDMA and TDMA modes, with emphasis on maximizing the bandwidth utilization capability of duobinary signalling. In a linear channel, single-
C. L. May, C. R. Cahn
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Correction of phase distortion in spatial heterodyne spectroscopy

Applied Optics, 2004
The detailed analysis of measured interferograms generally requires phase correction. Phase-shift correction methods are commonly used and well documented for conventional Fourier-transform spectroscopy. However, measured interferograms can show additional phase errors, depending on the optical path difference and signal frequency, which we call phase ...
Christoph R, Englert, John M, Harlander, Joel G, Cardon, Fred L, Roesler   +3 more
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The role of internal reflection in transskull phase distortion

Ultrasonics, 2001
Phase distortion due to reflection in transcranial ultrasound propagation is investigated. Understanding of these phase-dependent properties is motivated by efforts to construct a reliable prediction model for noninvasive ultrasound therapy in the brain.
G T, Clement, J, Sun, K, Hynynen
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Prediction of Distortion of Cylinders without Phase Transformations

Materialwissenschaft und Werkstofftechnik, 2006
The rule of Ameen whereby steel made cylinders with no phase transformations during quenching approach the spherical shape is contrary to the finding of Berger, who observes an elongation of thin and long work pieces. If the prediction of Ameen is correct, cylinders should decrease in length during heat treatment.
Frerichs, Friedhelm, Landek, Darko, Lubben, Thomas, Hoffmann, Franz, Zoch, Hans-Werner   +4 more
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Nonlinear estimation of phase in the presence of phase distortions

2011 XXXth URSI General Assembly and Scientific Symposium, 2011
In this paper we study the phase estimation problem in the presence of white noise and phase distortions on the basis of the Markovian technique of nonlinear processing of random fields. The emphasis is on the processing error dependence of the number of receivers.
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Effects of quadratic phase distortion on correlator performance

Applied Optics, 1992
The deformable mirror spatial light modulator (SLM) has an inherent distortion characteristic that can be approximated as a square-law transfer function. We examine the result of this distortion when this SLM is used in an optical correlator.
J L, Horner, P D, Gianino
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Distortion Reduction in Phase Modulation

IEEE Transactions on Aerospace and Electronic Systems, 1971
When a phase-modulated carrier of the form sin (wt+?) is multiplied by cos (wt), the recovered phase modulation is sin (?), which is a distorted version of . For small ?, the error is small, but is appreciable as A approaches unity or more. When ? is complicated (several subcarriers for example), the intermodulation can seriously degrade the system ...
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Distortion invariant pattern recognition with phase filters

Applied Optics, 1987
A recently developed approach for pattern recognition using spatial filters with reduced tolerance requirements is employed for the generation of filters containing mainly phase information. As anticipated, the recognition levels were decreased, but they remain adequate for unambiguous identification together with appreciable amounts of distortion ...
J, Rosen, J, Shamir
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Signal-dependent phase distortion in optical correlators

Applied Optics, 1987
We examine the effect of phase distortion inherent in a spatial light modulator on the performance of an optical correlator. We examine such areas as input plane distortion, input and Fourier plane distortion, effect of phase mismatch between these planes, and the effect of additive white noise.
J L, Horner, P D, Gianino
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