Results 271 to 280 of about 583,572 (316)
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A Modulated Helical Nanofilament Phase
Angewandte Chemie, 2013The modern study of the liquid crystal (LC) phases formed by bent-core molecules has led to many interesting and unexpected phenomena, including the first example of spontaneous reflection symmetry breaking and conglomerate formation in a bulk fluid phase.
Ethan, Tsai +8 more
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Coded Phase/Frequency Modulation
IEEE Transactions on Communications, 1986Channel coding combined with expanded signal sets has been shown [1] to improve error performance over uncoded modulation without expanding the bandwidth of the transmitted signals. In this paper, new coded modulation formats defined over an expanded set of signals varying both in phase and frequency are presented.
Roberto Padovani, Jack Keil Wolf
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(Continuous) Phase Modulation on the Hypersphere
IEEE Transactions on Wireless Communications, 2016We introduce phase modulation on the hypersphere (PMH) for load-modulated multiple-input multiple-output (MIMO) transmitters with a single central power amplifier. In PMH, the peak to average ratio of the sum power before pulse shaping is 1; thus, the central power amplifier of load-modulated MIMO transmitters does not require any back-off.
Mohammad Ali Sedaghat +2 more
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Modulation instability induced by cross-phase modulation
Physical Review Letters, 1987Modulation instability that leads to breakup of intense cw radiation into a train of ultrashort pulses during propagation in optical fibers occurs only in the presence of anomalous group-velocity dispersion. It is shown that a new kind of modulation instability can occur even in the normal-dispersion regime when two copropagating optical fields ...
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Quadrature frequency/phase modulation
IEEE Transactions on Communications, 1995A digital modulation method based on quadrature-carrier multiplexing of two N-dimensional biorthogonal signal sets is proposed. An embodiment of the proposed method referred to as quadrature frequency/phase modulation (QFPM), and its continuous phase modification CP QFPM, are described.
Solomon M. Fleisher, Shouxing Qu
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External phase-modulation interferometry
Applied Optics, 1996We analyze and test a laboratory benchtop version of a compound interferometric phase sensor, a Michelson interferometer whose output is combined coherently with a phase-modulated local oscillator beam tapped off the Michelson input beam. This configuration models a whole class of external-modulation interferometers designed to shift signals, obscured ...
M B, Gray +4 more
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Physica Scripta, 2002
We present a new simple and straightforward technique for solving the eigenvalue problem for initially phase modulated dark solitons in nonlinear dispersive media. Starting from the eigenvalue equations for the nonlinear Schrödinger equation which governs the dynamics of dark solitons, and introducing a set of new functions and a new variable for the ...
Shvartsburg, A. B. +2 more
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We present a new simple and straightforward technique for solving the eigenvalue problem for initially phase modulated dark solitons in nonlinear dispersive media. Starting from the eigenvalue equations for the nonlinear Schrödinger equation which governs the dynamics of dark solitons, and introducing a set of new functions and a new variable for the ...
Shvartsburg, A. B. +2 more
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A phase modulator with variable maximum phase deviation
IEEE Transactions on Communications, 1993A phase modulator, constructed with three Armstrong modulators, is presented. In this modulator, the maximum phase deviation can be extended up to pi without frequency multiplication. Numerical results of the signal distortion are given for several values of the maximum phase deviation and compared to other Armstrong type phase modulators. >
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The phase-modulated logistic map
Chaos: An Interdisciplinary Journal of Nonlinear Science, 2005We study the logistic mapping with the nonlinearity parameter varied through a delayed feedback mechanism. This history dependent modulation through a phaselike variable offers an enhanced possibility for stabilization of periodic dynamics. Study of the system as a function of nonlinearity and modulation parameters reveals new phenomena: In addition to
Nandi, Amitabha +3 more
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Phase correction of light modulators
Optics Letters, 1986A new and inexpensive holographic technique for measuring the phase errors of a two-dimensional spatial light modulator (SLM) is described, and experimental verification is provided. A new technique to correct spatial phase errors in any SLM is then detailed and experimentally demonstrated.
D, Casasent, S F, Xia
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