Results 211 to 220 of about 86,855 (259)

Sampling theorem for two dimensional fractional Fourier transform

Signal Processing, 2021
Abstract The fractional Fourier transform, which is a generalization of the Fourier transform, has become the focus of many research papers in recent years because of its applications in electrical engineering and optics. The fractional Fourier transform has been extended to n dimensions using tensor product of n copies of the one ...
Ahmed Zayed
exaly   +2 more sources

Two-dimensional affine generalized fractional Fourier transform

IEEE Transactions on Signal Processing, 2001
As the one-dimensional (1-D) Fourier transform can be extended into the 1-D fractional Fourier transform (FRFT), we can also generalize the two-dimensional (2-D) Fourier transform. Sahin et al. (see Appl. Opt., vol.37, no. 11, p.2130-41, 1998) have generalized the 2-D Fourier transform into the 2-D separable FRFT (which replaces each variable 1-D ...
Soo-Chang Pei
exaly   +2 more sources

Two-dimensional Fourier transform electronic spectroscopy

Journal of Chemical Physics, 2001
Two-dimensional Fourier transform electronic spectra of the cyanine dye IR144 in methanol are used to explore new aspects of optical 2D spectroscopy on a femtosecond timescale. The experiments reported here are pulse sequence and coherence pathway analogs of the two-dimensional magnetic resonance techniques known as COSY (correlated spectroscopy) and ...
David Jonas, Jonas David M
exaly   +2 more sources

Two‐dimensional sparse fractional Fourier transform and its applications

Signal Processing, 2022
Deyun Wei
exaly   +2 more sources

Two-Dimensional Fourier Transform

2021
In this chapter, we present elements for calculating and plotting discrete two-dimensional Fourier transforms. Figure 17-1 provides two screenshots from an Android cell phone. The one on the left shows a rectangular, two-dimensional spatial-function. The right screenshot shows the corresponding discrete Fourier transform obtained using this program.
Moisés Cywiak, David Cywiak
openaire   +1 more source

Two-dimensional Fourier transform rheology

Journal of Rheology, 2001
A two-dimensional Fourier transformation (FT) rheology experiment is presented that separates the relaxation dynamics of different contributions to the stress relaxation, here specifically for entangled polymers. This experiment has the overall form of discrete large amplitude oscillations and consists of multiple step shear experiments.
van Dusschoten, D., Wilhelm, M., Spiess, H.   +2 more
openaire   +2 more sources

Two dimensional properties of discrete fourier transform

Calcolo, 1976
Two significant two-dimensional decomposition rules for the Discret Fourier Transform of a set of N data (N=2p) are considered. It is shown that the two-dimensional processing performed according to such rules involves exactly the same operations on the same data as the one-dimensional processing.
Bongiovanni G., Corsini P., Frosini G.
openaire   +3 more sources

Stereoscopic Two-Dimensional Fourier Transform

2021
In this chapter, we present elements for calculating and plotting stereoscopic two-dimensional Fourier transforms. Figure 18-1 provides two screenshots from an Android cell phone. On the left is a two-dimensional spatial function, and on the right is a corresponding Fourier transform obtained with the program.
Moisés Cywiak, David Cywiak
openaire   +1 more source

Two-dimensional Fourier-transform spectrometer

Optical Society of America Annual Meeting, 1990
A Fourier-transform spectrometer has been built by using a common-path ring design for the as interferometer and a two-dimensional charge-coupled device array for the detector. The detector records the Fourier-Fraunhofer hologram that is produced by the sheared images of the source.
Joel C. Berlinghieri, Russell O. Hilleke
openaire   +1 more source

Two-Dimensional Radon-Fourier Transformer

Optical Engineering, 1985
The well-known central-slice, or projection-slice, theorem states that the Radon transform can be used to reduce a two-dimensional Fourier transform to a series of one-dimensional Fourier transforms. In this paper we describe a practical system for implementing this theorem.
Anthony J. Ticknor, Roger L. Easton, Harrison H. Barrett   +2 more
openaire   +1 more source