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Ponderomotive plasma lenses for holography by Gaussian beams. [PDF]

Sci Rep
Alilou S, Shahrassai L, Sobhanian S.
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Uncertainty principles for the quadratic‐phase Fourier transforms

Mathematical methods in the applied sciences, 2021
The quadratic‐phase Fourier transform (QPFT) is a recent addition to the class of Fourier transforms and embodies a variety of signal processing tools including the Fourier, fractional Fourier, linear canonical, and special affine Fourier transform.
F. Shah, K. S. Nisar, Waseem Z. Lone, Azhar Y. Tantary   +3 more
semanticscholar   +1 more source

Silhouette-free interference-based multiple-image encryption using cascaded fractional Fourier transforms

Optics and lasers in engineering, 2019
An optical approach of silhouette-free multiple-image encryption based on interference is proposed, with two layers to enhance the level of security. In the first layer, a group of plain images are encoded into an amplitude distribution, called interim ...
L. Sui, Zhang-Shu Xiao, Chongtian Huang, Ailing Tian, A. Asundi   +4 more
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Fractional Fourier transforms and their optical implementation II

Journal of the Optical Society of America A: Optics and Image Science, and Vision, 1993
Haldun M Ozaktas
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Analysis and comparison of discrete fractional fourier transforms

Signal Processing, 2019
The fractional Fourier transform (FRFT) is a powerful tool for time-varying signal analysis. There exist various discrete fractional Fourier transforms (DFRFTs); in this paper, we systematically analyze and compare the main DFRFT types: sampling-type ...
Xinhua Su, R. Tao, Xuejing Kang
semanticscholar   +1 more source

On Fourier Series on the Torus and Fourier Transforms

Mathematical Notes, 2021
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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The Fourier transform and the discrete Fourier transform

Inverse Problems, 1989
This paper gives an error bound in computing the Fourier transform for a square summable function by means of the discrete Fourier transform. In detail description, the error bound depends on the number of samples, the interval where the samples are taken, the interval where the Fourier transform is being approximated, the local averaging in the time ...
Auslander, Louis, Grünbaum, F. Alberto
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The Fourier Transform

Scientific American, 1989
To calculate a transform, just listen. The ear automatically performs the calculation, which the intellect can execute only after years of mathematical education. The ear formulates a transform by converting sound-the waves of pressure traveling through time and the atmosphere-into a spectrum, a description of the sound as a series of volumes at ...
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Using NFFT 3---A Software Library for Various Nonequispaced Fast Fourier Transforms

ACM Transactions on Mathematical Software, 2009
Stefan Kunis, Daniel Potts
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RNS Fourier transforms

ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing, 2003
A novel approach to the definition of the roots of unity in the RNS (residue number system) is presented. The definition is based on a suitable polar representation of the complex residues. The resulting RNS Fourier transform provides an algorithm for performing circular convolutions characterized by flexibility in terms of length, computational cost ...
Pietro Burrascano, Gian Carlo Cardarilli, Roberto Lojacono, Giuseppe Martinelli, Mario Salerno   +4 more
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