Results 211 to 220 of about 47,726 (260)
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Phase Distortion of Averaged Electroencepha
Archives of Otolaryngology - Head and Neck Surgery, 1974Analog filters employed in most averaged electroencephalic response (AER) recording systems impose some phase distortion on recorded AER. Phase distortion of the response results in a real time shift of peak latencies. The extent of this distortion, in general, is determined by the cutoff frequencies of the filter band in relation to the spectrum of ...
R. H. Lane +5 more
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Phase Distortion Study (Phase B)
1977Abstract : 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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Composite pulses without phase distortion
Journal of Magnetic Resonance (1969), 1985Abstract Composite pulses for broadband spin excitation over large ranges of radiofrequency field amplitudes and resonance offsets are presented. They are derived according to a previously presented method based on the Magnus expansion in the manner of coherent averaging theory. It is shown theoretically and in simulations that these composite pulses
R Tycko, H.M Cho, E Schneider, A Pines
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Signal-dependent phase distortion in optical correlators
Applied Optics, 1987We 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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Distortion invariant pattern recognition with phase filters
Applied Optics, 1987A 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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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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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 series echography with prior waveform distortion for evaluating posterior waveform distortion
IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 2006We describe a pulse-echo ultrasound method for measuring nonlinear waveform distortion. First, two artificially distorted ultrasound pulses, one of which is transformed into the other by using a linear transform, are prepared prior to the measurement. The linear relationship does not hold for nonlinear propagation.
Ayumu, Matani, Takayuki, Shigeno
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Distortion Reduction in Phase Modulation
IEEE Transactions on Aerospace and Electronic Systems, 1971When 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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Phase Distortion in Telephone Apparatus*
Bell System Technical Journal, 1930This paper shows that if, over its transmitting range, the phase shift, B, in radians, of a four-terminal network may be written B = a 0 + a 1 ω (ω = 2πx frequency in cycles per second), there is no phase distortion if a 0 = N, N being any integer. However, there is a delay, for any signal, given by dB/dω = a 1 (seconds).
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Phase distortion in operational amplifiers
Mathematics and Computers in Simulation, 1962The stray capacities in the input and feedback paths of an operational amplifier, its finite bandwidth and d.c. gain effectively narrow the bandwidth of an amplifier causing amplitude and phase errors in the computer solutions. A given degree of accuracy consequently becomes more difficult to obtain with an amplifier when used in a high-speed ...
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