Results 71 to 80 of about 257,484 (138)
An Illustrated Introduction to the Truncated Fourier Transform [PDF]
arXiv, 2016 The Truncated Fourier Transform (TFT) is a variation of the Discrete Fourier Transform (DFT/FFT) that allows for input vectors that do NOT have length $2^n$ for $n$ a positive integer. We present the univariate version of the TFT, originally due to Joris van der Hoeven, heavily illustrating the presentation in order to make these methods accessible to ...
arxiv
IEEE Access, 2019 In this paper, we investigate the performance of a discrete Fourier transform (DFT)-spread OFDM signal in an intensity-modulation/direct-detection system.
Yupeng Li, Jiawei Han, Xiaonan Zhao
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The discrete Fourier transform of $r$-even functions [PDF]
Acta Univ. Sapientiae, Math. 3 (2011), 5--25, 2010 We give a detailed study of the discrete Fourier transform (DFT) of $r$-even arithmetic functions, which form a subspace of the space of $r$-periodic arithmetic functions. We consider the DFT of sequences of $r$-even functions, their mean values and Dirichlet series. Our results generalize properties of the Ramanujan sum.
arxiv
Water Science and Technology, 2014 The objective of this work is to introduce a forecasting method for UV-Vis spectrometry time series that combines principal component analysis (PCA) and discrete Fourier transform (DFT), and to compare the results obtained with those obtained by using DFT.
Andrés Torres +2 more
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VLSI Architecture for Novel Hopping Discrete Fourier Transform Computation
IEEE Access, 2018 The hopping discrete Fourier transform (HDFT) is a new method applied for time-frequency spectral analysis of time-varying signals. In the implementation of HDFT algorithms, the updating vector transform (UVT) plays a key role, and therefore a novel ...
Wen-Ho Juang +3 more
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An Example of non-quenched Convergence in the Conditional CLT for Discrete Fourier Transforms [PDF]
arXiv, 2014 A recent result by Barrera and Peligrad shows that the quenched Central Limit Theorem holds for the discrete Fourier transforms (DFT) of a stationary process in $L^2$ if a "random" centering is used. In this note we show that this is a necessary condition by providing an example of a process satisfying the hypothesis of such theorem for which the DFT ...
arxiv
Jurnal Informatika, 2017 Penyebaran data digital melalui internet memiliki sisi positif dan negatif, terutama bagi pemilik asli citra digital. Penanganan permasalahan tersebut dapat digunakan teknik yang dinamakan image watermarking. Dalam paper ini diimplementasikan suatu teknik image watermarking pada citra digital dengan menggunakan metode Discrete Fourier Transform (DFT ...
Murinto, Tri Kasihno
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Matrix-Vector Based Fast Fourier Transformations on SDR Architectures [PDF]
Advances in Radio Science, 2008 Today Discrete Fourier Transforms (DFTs) are applied in various radio standards based on OFDM (Orthogonal Frequency Division Multiplex). It is important to gain a fast computational speed for the DFT, which is usually achieved by using specialized Fast ...
Y. He +3 more
doaj
Minimal Hermite-type eigenbasis of the discrete Fourier transform [PDF]
arXiv, 2017 There exist many ways to build an orthonormal basis of $\mathbb{R}^N$, consisting of the eigenvectors of the discrete Fourier transform (DFT). In this paper we show that there is only one such orthonormal eigenbasis of the DFT that is optimal in the sense of an appropriate uncertainty principle.
arxiv
Multiplierless discrete Fourier transform based on moments
Tongxin xuebao, 2009 A novel algorithm to perform Discrete Fourier Transform（DFT） multiplierlessly was proposed.First, by modular mapping and truncating Taylor series expansion, the DFT was expressed in the form of the product of the constants and discrete moments.Second, by
LIU Zhen-bing +2 more
doaj +2 more sources