Journal ArticleDOI
Some fundamental properties of speckle
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TLDR
In this paper, the distribution of scale sizes in a speckle pattern (i.e., the Wiener spectrum) is investigated from a physical point of view, and it is shown that adding M uncorrelated speckles on an intensity basis can reduce the contrast by 1/√M.Abstract:
A speckle pattern formed in polarized monochromatic light may be regarded as resulting from a classical random walk in the complex plane. The resulting irradiance fluctuations obey negative exponential statistics, with ratio of standard deviation to mean (i.e., contrast) of unity. Reduction of this contrast, or smoothing of the speckle, requires diversity in polarization, space, frequency, or time. Addition of M uncorrelated speckle patterns on an intensity basis can reduce the contrast by 1/√M. However, addition of speckle patterns on a complex amplitude basis provides no reduction of contrast. The distribution of scale sizes in a speckle pattern (i.e., the Wiener spectrum) is investigated from a physical point of view.read more
Citations
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Journal ArticleDOI
Speckle filtering of synthetic aperture radar images : a review
TL;DR: A critical evaluation of speckle suppression filters is made using a simulated SAR image as well as airborne and spaceborne SAR images and computational efficiency and implementation complexity are compared.
Journal ArticleDOI
A versatile wavelet domain noise filtration technique for medical imaging
TL;DR: A robust wavelet domain method for noise filtering in medical images that adapts itself to various types of image noise as well as to the preference of the medical expert; a single parameter can be used to balance the preservation of (expert-dependent) relevant details against the degree of noise reduction.
Iterative Weighted Maximum Likelihood Denoising with Probabilistic Patch-Based Weights c 2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.
TL;DR: In this article, a more general and statistically grounded similarity criterion is proposed which depends on the noise distribution model, and denoising process is expressed as a weighted maximum likelihood estimation problem where the weights are derived in a data-driven way.
Journal ArticleDOI
Improved Sigma Filter for Speckle Filtering of SAR Imagery
TL;DR: The bias problem is solved by redefining the sigma range based on the speckle probability density functions, and a target signature preservation technique is developed to mitigate the problems of blurring and depressing strong reflective scatterers.
Journal ArticleDOI
Light fields in complex media: Mesoscopic scattering meets wave control
Stefan Rotter,Sylvain Gigan +1 more
TL;DR: In this article, a review summarizes how insights from mesoscopic scattering theory have direct relevance for optical wave control experiments and vice versa, and the results are expected to have an impact on a number of fields ranging from biomedical imaging to nanophotonics, quantum information, and communication technology.
References
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ReportDOI
Statistical properties of laser sparkle patterns
TL;DR: In this article, the first order statistics of the observed electric-field strength, the observed light intensity, and observed light phase are examined, and the autocorrelation functions of the complex field and intensity processes are investigated, and that of the electric field is found to be proportional to the Fourier transform of the light intensity distribution incident on the scattering surface.
Book ChapterDOI
Statistical Properties of Laser Speckle Patterns
TL;DR: In this article, the first-order statistics of the complex amplitude, intensity and phase of speckle are derived for a free-space propagation geometry and for an imaging geometry.
Journal ArticleDOI
Some Aspects of Diffraction Theory and their Application to the Ionosphere
TL;DR: In this paper, the Fourier approach is extended to deal with problems of ''random'' diffraction, for which purpose the use of auto-correlation functions is introduced and explained in physical terms.
Investigation of molecular motions in supercooled liquids by Mossbauer scattering D C Champeney and F W D Woodhams Some Aspects of Diffraction Theory and their Application to the Ionosphere
J A Ratcliffe,D C Champeney +1 more
TL;DR: In this article, the Fourier approach is extended to deal with problems of ''random'' diffraction, for which purpose the use of auto-correlation functions is introduced and explained in physical terms.
Journal ArticleDOI
XII. On the resultant of a large number of vibrations of the same pitch and of arbitrary phase
TL;DR: In this article, the resultant of a large number of vibrations of the same pitch and of arbitrary phase is discussed. But the authors focus on the effect of the phase of the vibrations.