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On the Signal-to-Noise Ratio for Optical Heterodyne Detection
Journal of Applied Physics, 1972The conventional result for the signal-to-noise ratio in an optical heterodyne detector is shown to apply to the mixing of a stable local oscillator with any radiation field which gives rise to a stationary narrow-band i.f. signal. The result is explicitly demonstrated for radiation scattered from a diffuse target, which may be represented as a narrow ...
Malvin C. Teich, R. Y. Yen
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Analysis of signal-to-noise ratio in optical receivers
6th International Conference on Telecommunications in Modern Satellite, Cable and Broadcasting Service, 2003. TELSIKS 2003., 2004The paper describes low noise preamplifiers designed for optical detectors. Analysis of operating conditions affecting signal to noise ratio has been carried out. Each preamplifier was carefully optimised to work with particular type of the detector.
E. Sędek +3 more
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Measuring the Optical Signal-to-Noise Ratio in Agile Optical Networks
OFC/NFOEC 2007 - 2007 Conference on Optical Fiber Communication and the National Fiber Optic Engineers Conference, 2007We have proposed an improved OSNR measurement technique called optical polarization splitting based on the polarization-nulling method. The test results with Tellabs ultra high speed networks showed that the proposed technique could measure the OSNR accurately at all modulation formats even when the signal was significantly depolarized due to PMD and ...
W. Moench, Julia Y. Larikova
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Signal-to-noise ratio in optical heterodyne detection for Gaussian fields
Applied Optics, 1978The signal-to-noise ratio of optical heterodyne detection is discussed for Gaussian fields. The ratio of the aperture radius a of the detector to the smallest spot size w(s) of the signal has serious effects on the SNR. The conditions that maximize the SNR are obtained for a given signal or local oscillator field.
Takashi Takenaka +2 more
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Signal-to-noise ratio calculation in a moving-optical-wedge spectrometer
Applied Optics, 2012In this paper we study the signal-to-noise ratio degradation in a moving-optical-wedge interferometer when used as an optical spectrometer. Both the mechanical vibration and temperature fluctuation effects are studied, and the effects are compared to their counterparts in a conventional Michelson interferometer.
Tarek A. Al-Saeed, Diaa Khalil
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Signal-to-noise ratio of a semiconductor optical-amplifier-based optical phase shifter
Optics Letters, 2009We report an experimental characterization of additive noise from a single-stage phase shifter based on slow and fast light propagation in a bulk semiconductor optical amplifier. We examine the influence of redshifted sideband suppression and optical input power on the signal-to-noise ratio (SNR) of the detected signal. We conclude that in spite of the
Sean P. O Duill +2 more
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Modal noise-limited signal-to-noise ratios in multimode optical fibers
Applied Optics, 1983The problem of signal degradation due to spatial filtration in graded-index fibers excited by single-mode lasers is considered. In particular, a computer simulation of the interfering pattern is used to predict the signal-to-noise ratios which would be measured given some degree of vignetting at the detector end of the fiber.
Audun Weierholt, Alan R. Mickelson
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Signal-to-noise-ratio expressions in optical diffusion tomography
Journal of the Optical Society of America A, 2002Optical diffusion tomography is a technology that is employed to obtain images of the heterogeneous nature of turbid media by using optical radiation. Noise ultimately limits the achievable spatial resolution in these reconstructed images; therefore it is of interest to develop signal-to-noise-ratio expressions that relate spatial resolution in the ...
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Instantaneous signal-to-noise ratio of time-domain optical coherence tomography
SPIE Proceedings, 2005We model the photocurrent of a depth-scan (A-scan) from an optical coherence tomography (OCT) system, using a linearly polarized thermal source, as an electronically filtered doubly-stochastic Poisson process, and we obtain its time-varying second-order statistics. We derive an expression for the instantaneous signal-to-noise ratio (SNR) of time-domain
Sherif S. Sherif +2 more
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Maximization of Signal-to-Noise Ratio in an Optical Filter
SIAM Journal on Applied Mathematics, 1969where xeE , S = {xeE :0 0, (ii) B is symmetric and positive definite, (iii) # > 0. This problem arises in the maximization of the signal-to-noise ratio in a spectral filter for infrared detectors (see [7]). The term 2 represents the incoming signal and + ,B is the variance of the background signal.
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