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Scalable integrated two-dimensional Fourier-transform spectrometry [PDF]
Nature CommunicationsIntegrated spectrometers offer the advantages of small sizes and high portability, enabling new applications in industrial development and scientific research.
Hongnan Xu +3 more
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Discrete two dimensional Fourier transform in polar coordinates part II: numerical computation and approximation of the continuous transform [PDF]
PeerJ Computer Science, 2020 The theory of the continuous two-dimensional (2D) Fourier Transform in polar coordinates has been recently developed but no discrete counterpart exists to date.
Xueyang Yao, Natalie Baddour
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Two-dimensional Fourier-transform Spectroscopy of Potassium Vapor [PDF]
Conference on Lasers and Electro-Optics 2010, 2010 Optical two-dimensional Fourier-transformed (2DFT) spectroscopy is used to study the coherent optical response of potassium vapor in a thin transmission cell.
Bristow, A. D. +3 more
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A New Discretization Scheme for the Non-Isotropic Stockwell Transform
Mathematics, 2023 To avoid the undesired angular expansion of the sampling grid in the discrete non-isotropic Stockwell transform, in this communication we propose a scale-dependent discretization scheme that controls both the radial and angular expansions in unison ...
Hari M. Srivastava +2 more
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Nonseparable two-dimensional fractional Fourier transform [PDF]
Applied Optics, 1998 Previous generalizations of the fractional Fourier transform to two dimensions assumed separable kernels. We present a nonseparable definition for the two-dimensional fractional Fourier transform that includes the separable definition as a special case. Its digital and optical implementations are presented.
Sahin, A., Kutay, M. A., Ozaktas, H. M.
openaire +6 more sources
Sliding signal processing in telecommunication networks based on two-dimensional discrete Fourier transform [PDF]
ITM Web of Conferences, 2019 A method of vertical sliding processing of two-dimensional discrete signals in the spatial frequency domain is proposed — a method of fast vertically sliding two-dimensional discrete Fourier transform.
Ponomarev Vladimir +3 more
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Mathematics, 2023 In this paper, we present a novel integral transform known as the one-dimensional quaternion quadratic-phase Fourier transform (1D-QQPFT). We first define the one-dimensional quaternion quadratic-phase Fourier transform (1D-QQPFT) of integrable (and ...
Mohammad Younus Bhat +3 more
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A variational restriction theorem [PDF]
, 2020 We establish variational estimates related to the problem of restricting the Fourier transform of a three-dimensional function to the two-dimensional Euclidean sphere.
Kovač, Vjekoslav +1 more
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IEEE Access, 2021 The waveguide invariant is classically considered as constant in shallow water and can be utilized to estimate the source range. When the environment is variable, the error between the estimated range and the true range fluctuates and becomes unstable ...
Yuan Yao +3 more
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Arbitrary Sampling Fourier Transform and Its Applications in Magnetic Field Forward Modeling
Applied Sciences, 2022 Numerical simulation and inversion imaging are essential in geophysics exploration. Fourier transform plays a vital role in geophysical numerical simulation and inversion imaging, especially in solving partial differential equations.
Shikun Dai +4 more
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