Browsing by Keywords "Fourier transforms"
Now showing items 2140 of 74

Estimation of Spurious Radiation from Microstrip Etches Using ClosedForm Green’s Functions
(IEEE, 1992)The problem of spurious radiation from electronic packages is considered in this paper by investigating the power radiated from microstrip etches that are excited by arbitrarilylocated current sources, and terminated by ... 
Exact solution for scalar diffraction between tilted and translated planes using impulse functions over a surface
(Optical Society of America, 20110204)The diffraction relation between a plane and another plane that is both tilted and translated with respect to the first one is revisited. The derivation of the result becomes easier when the impulse function over a surface ... 
Filtering in fractional Fourier domains and their relation to chirp transforms
(IEEE, 199404)Fractional Fourier transforms, which are related to chirp and wavelet transforms, lead to the notion of fractional Fourier domains. The concept of filtering of signals in fractional domains is developed, revealing that ... 
Fourier transforms of fractional order and their optical interpretation
(Elsevier, 1993)Fourier transforms of fractional order a are defined in a manner such that the common Fourier transform is a special case with order a=1. An optical interpretation is provided in terms of quadratic graded index media and ... 
The fractional Fourier domain decomposition
(Elsevier, 1999)We introduce the fractional Fourier domain decomposition. A procedure called pruning, analogous to truncation of the singularvalue decomposition, underlies a number of potential applications, among which we discuss fast ... 
The fractional fourier transform
(IEEE, 2001)A brief introduction to the fractional Fourier transform and its properties is given. Its relation to phasespace representations (time or spacefrequency representations) and the concept of fractional Fourier domains are ... 
The Fractional Fourier transform and harmonic oscillation
(Springer, 2002)The athorder fractional Fourier transform is a generalization of the ordinary Fourier transform such that the zerothorder fractional Fourier transform operation is equal to the identity operation and the firstorder ... 
The fractional fourier transform and its applications to image representation and beamforming
(ASME, 200309)The ath order fractional Fourier transform operator is the ath power of the ordinary Fourier transform operator. We provide a brief introduction to the fractional Fourier transform, discuss some of its more important ... 
Fractional Fourier transform as a tool for analyzing beam propagation and spherical mirror resonators
(Optical Society of America, 1994)The complex amplitude distributions on two spherical reference surfaces of given curvature and spacing are simply related by a fractional Fourier transform. The order of the fractional Fourier transform is proportional to ... 
Fractional fourier transform in time series prediction
(IEEE, 20221209)Several signal processing tools are integrated into machine learning models for performance and computational cost improvements. Fourier transform (FT) and its variants, which are powerful tools for spectral analysis, are ... 
Fractional Fourier transforms and their optical implementation. II
(Optical Society of America, 1993)The derivation of a linear transform kernel for fractional Fourier transforms is presented. Discussed in direct relation to fractal Fourier transforms are spatial resolution and the spacebandwidth product for propagation ... 
Fractional free space, fractional lenses, and fractional imaging systems
(OSA  The Optical Society, 2003)Continuum extensions of common dual pairs of operators are presented and consolidated, based on the fractional Fourier transform. In particular, the fractional chirp multiplication, fractional chirp convolution, and ... 
FTIR studies of vitamin EcholesterolDPPC membrane interactions in CH2 region
(SpringerVerlag, 1996)Binary and ternary mixtures of αtocopherol (αT), cholesterol and dipalmitoyl phosphatidylcholine (DPPC) in the form of multilamellar liposomes have been investigated by Fourier Transform Infrared Spectroscopy (FTIR). ... 
Fundamental structure of Fresnel diffraction: Longitudinal uniformity with respect to fractional Fourier order
(Optical Society of America, 20111224)Fresnel integrals corresponding to different distances can be interpreted as scaled fractional Fourier transformations observed on spherical reference surfaces. Transverse samples can be taken on these surfaces with ... 
Fundamental structure of Fresnel diffraction: natural sampling grid and the fractional Fourier transform
(Optical Society of America, 20110629)Fresnel integrals corresponding to different distances can be interpreted as scaled fractional Fourier transformations observed on spherical reference surfaces. We show that by judiciously choosing sample points on these ... 
Generalization of timefrequency signal representations to joint fractional Fourier domains
(IEEE, 200509)The 2D signal representations of variables rather than time and frequency have been proposed based on either Hermitian or unitary operators. As an alternative to the theoretical derivations based on operators, we propose ... 
Generalized timebandwidth product optimal shorttime fourier transformation
(IEEE, 200205)By extending the timebandwidth product concept to fractional Fourier domains, a generalized timebandwidth product (GTBP) is introduced. The GTBP provides a rotation independent measure for the support of the signals in ... 
High resolution timefrequency analysis by fractional domain warping
(IEEE, 200105)A new algorithm is proposed to obtain very high resolution timefrequency analysis of signal components with curved timefrequency supports. The proposed algorithm is based on fractional Fourier domain warping concept ... 
Highspeed 1.3 μm GaAs internal photoemission resonant cavity enhanced photodetector
(IEEE, 2000)Resonant cavity enhanced (RCE) photodetectors offer the possibility of overcoming the low quantum efficiency limitation of conventional photodetectors. The RCE detectors are based on the enhancement of the optical field ... 
Highspeed InGaAs based resonant cavity enhanced pin photodiodes
(IEEE, 2001)Highspeed InGaAs based resonant cavity enhanced photodiodes were discussed. The responses of the photodiodes was measured under high incident optical powers. Bandwidthefficiency (BWE) product was used to measure the ...