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The Fast Fourier Transform (FFT) is a fundamental tool for signal analysis, widely used across various fields. However, traditional FFT methods encounter challenges in adjusting the frequency bin interval, which may impede accurate spectral…

Data Structures and Algorithms · Computer Science 2024-03-27 Haichao Xu

Pseudo-spectral method is one of the most accurate techniques for simulating turbulent flows. Fast Fourier transform (FFT) is an integral part of this method. In this paper, we present a new procedure to compute FFT in which we save…

Mathematical Software · Computer Science 2014-06-24 A. G. Chatterjee , M. K. Verma , M. Chaudhuri

The state-of-the-art automotive radars employ multidimensional discrete Fourier transforms (DFT) in order to estimate various target parameters. The DFT is implemented using the fast Fourier transform (FFT), at sample and computational…

Signal Processing · Electrical Eng. & Systems 2018-01-16 Shaogang Wang , Vishal M. Patel , Athina Petropulu

The Fractional Fourier Transform (FRT) corresponds to an arbitrary-angle rotation in the phase space, e.g. the time-frequency (TF) space, and generalizes the fundamentally important Fourier Transform. FRT applications range from classical…

Optics · Physics 2024-03-06 Michał Lipka , Michał Parniak

We present an efficient, fast and robust Nonlinear Fourier Transform (NFT) algorithm to detect eigenvalues of the discrete spectrum. It outperforms other known NFT algorithms as it detects the eigenvalues from the continuous spectrum, the…

Information Theory · Computer Science 2018-12-10 Vahid Aref , Son T. Le , Henning Buelow

We propose a method for tailoring the frequency spectrum of bright squeezed vacuum by generating it in a nonlinear interferometer, consisting of two down-converting nonlinear crystals separated by a dispersive medium. Due to a faster…

Quantum Physics · Physics 2016-01-20 T. Sh. Iskhakov , S. Lemieux , A. Perez , R. W. Boyd , G. Leuchs , M. Chekhova

We present an approach for improving spatial frequency sampling in active incoherent millimeter-wave (AIM) imaging systems using frequency diversity. AIM imaging relies on active transmission of spatio-temporally incoherent signals to…

Signal Processing · Electrical Eng. & Systems 2025-03-12 Jorge R. Colon-Berrios , Jeffrey A. Nanzer

This paper details the purpose, difficulties, theory, implementation, and results of developing a Fast Fourier Transform (FFT) using the prime factor algorithm on an embedded system. Many applications analyze the frequency content of…

Hardware Architecture · Computer Science 2025-01-22 Josh Vernon , D. G. Perera

In this paper, we consider a method for fast numerical computation of the Fourier transform of a slowly decaying function with given accuracy in given ranges of the frequency. In these decades, some useful formulas for the Fourier transform…

Numerical Analysis · Mathematics 2015-07-28 Ken'ichiro Tanaka

In computational optics, numerical modeling of diffraction between arbitrary planes offers unparalleled flexibility. However, existing methods suffer from the trade-off between computational accuracy and efficiency. To resolve this dilemma,…

Optics · Physics 2023-12-12 Yiwen Hu , Xin Liu , Shi Feng , Xu Liu , Xiang Hao

Non-uniform fast Fourier Transform (NUFFT) and inverse NUFFT (INUFFT) algorithms, based on the Fast Multipole Method (FMM) are developed and tested. Our algorithms are based on a novel factorization of the FFT kernel, and are implemented…

Numerical Analysis · Computer Science 2016-11-30 Nail A. Gumerov , Ramani Duraiswami

The nonlinear Fourier transform (NFT) has recently gained significant attention in fiber optic communications and other engineering fields. Although several numerical algorithms for computing the NFT have been published, the design of…

Signal Processing · Electrical Eng. & Systems 2019-10-17 Shrinivas Chimmalgi , Peter J. Prins , Sander Wahls

A Discrete Fourier Transform Method (DFTM) for discrimination between the signal of neutrons and gamma rays in organic scintillation detectors is presented. The method is based on the transformation of signals into the frequency domain…

Instrumentation and Detectors · Physics 2016-11-03 M. J. Safari , F. Abbasi Davani , H. Afarideh , S. Jamili , E. Bayat

We propose and experimentally validate a joint estimation method for chromatic dispersion and time-frequency offset based on the fractional Fourier transform, which reduces computational complexity by more than 50% while keeping estimation…

Signal Processing · Electrical Eng. & Systems 2024-11-08 Guozhi Xu , Zekun Niu , Lyu Li , Weisheng Hu , Lilin Yi

We present a new method for the generation of atmospheric turbulence phase screens based on the frequency shift property of the Fourier transform. This method produces low spatial frequency distortions without additional computation time…

Optics · Physics 2020-01-08 Daniel A. Paulson , Chensheng Wu , Christopher C. Davis

Femtosecond interferometry combined with acousto-optical phase modulation is an effective approach to implement various types of coherent nonlinear and multidimensional spectroscopy schemes. The high sensitivity of this method has recently…

Atomic Physics · Physics 2025-02-24 Friedemann Landmesser , Nicolai Gölz , Ulrich Bangert , Tobias Sixt , Lukas Bruder

In this paper we explain how to use the Fast Fourier Transform (FFT) to solve partial differential equations (PDEs). We start by defining appropriate discrete domains in coordinate and frequency domains. Then describe the main limitation of…

Numerical Analysis · Mathematics 2025-07-31 Daniela Rodriguez-Lara , Ivan Alvarez-Rios , Francisco S. Guzman

Consider the scattering of a time-harmonic plane wave by heterogeneous media consisting of linear or nonlinear point scatterers and extended obstacles. A generalized Foldy-Lax formulation is developed to take fully into account of the…

Numerical Analysis · Mathematics 2017-06-22 Jun Lai , Ming Li , Peijun Li , Wei Li

We develop the uniform sparse Fast Fourier Transform (usFFT), an efficient, non-intrusive, adaptive algorithm for the solution of elliptic partial differential equations with random coefficients. The algorithm is an adaption of the sparse…

Numerical Analysis · Mathematics 2022-09-05 Lutz Kämmerer , Daniel Potts , Fabian Taubert

The special affine Fourier transform (SAFT) is a promising tool for analyzing non-stationary signals with more degrees of freedom. However, the SAFT fails in obtaining the local features of non-transient signals due to its global kernel and…

Functional Analysis · Mathematics 2020-06-11 Firdous A. Shah , Azhar Y. Tantary , Aajaz A. Teali