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One of the major challenges of employing a dual-frequency phase-shifting algorithm for phase retrieval is its sensitivity to noise. Yun et. al [H Yun, B Li, S Zhang. 2017] proposed a dual-frequency method based on the Fourier transform…

Instrumentation and Detectors · Physics 2018-05-23 Minmin Wang , Canlin Zhou , Shuchun Si , Zhenkun Lei , Xiaolei Li , Hui Li , YanJie Li

The cylindrical Taylor Interpolation through FFT (TI-FFT) algorithm for computation of the near-field and far-field in the quasi-cylindrical geometry has been introduced. The modal expansion coefficient of the vector potentials ${\bf F}$…

Signal Processing · Electrical Eng. & Systems 2020-07-06 Shaolin Liao

Prior works on near-field beam training have mostly assumed dedicated polar-domain codebook and on-grid range estimation, which, however, may suffer long training overhead and degraded estimation accuracy. To address these issues, we…

Information Theory · Computer Science 2024-05-08 Xun Wu , Changsheng You , Jiapeng Li , Yunpu Zhang

Fourier transform methods are used to analyze functions and data sets to provide frequencies, amplitudes, and phases of underlying oscillatory components. Fast Fourier transform (FFT) methods offer speed advantages over evaluation of…

Data Analysis, Statistics and Probability · Physics 2015-07-08 Elya Courtney , Michael Courtney

For extremely large-scale arrays (XL-arrays), the discrete Fourier transform (DFT) codebook, conventionally used in the far-field, has recently been employed for near-field beam training. However, most existing methods rely on the…

Signal Processing · Electrical Eng. & Systems 2026-03-27 Jiapeng Li , Changsheng You , Guoliang Cheng , Haobin Sun , Chao Zhou , Linglong Dai

Preserving accuracy is a challenging issue in super resolution images. In this paper, we propose a new FFT based image registration algorithm and a sparse based super resolution algorithm to improve the accuracy of super resolution image.…

Computer Vision and Pattern Recognition · Computer Science 2014-07-15 Archana Vijayan , Vincy Salam

Time-frequency representations, such as the short-time Fourier transform (STFT), are fundamental tools for analyzing non-stationary signals. However, their ability to achieve sharp localization in both time and frequency is inherently…

Signal Processing · Electrical Eng. & Systems 2026-04-17 David Valdivia , Elsa Cazelles , Cédric Févotte

Traditional data collection from sensors produce a lot of data, which lead to constant power consumption and require more storage space. This study proposes an algorithm for a data acquisition and processing method based on Fourier…

Signal Processing · Electrical Eng. & Systems 2026-01-19 Nursultan Daupayev , Christian Engel , Ricky Bendyk , Soeren Hirsch

We have developed an algorithm for transferring radiation in three-dimensional space. The algorithm computes radiation source and sink terms using the Fast Fourier Transform (FFT) method, based on a formulation in which the integral of any…

Astrophysics · Physics 2009-11-07 Renyue Cen

In this article, we present an $O(N \log N)$ rapidly convergent algorithm for the numerical approximation of the convolution integral with radially symmetric weakly singular kernels and compactly supported densities. To achieve the reduced…

Numerical Analysis · Mathematics 2021-07-09 Awanish Kumar Tiwari , Ambuj Pandey , Jagabandhu Paul , Akash Anand

The ability to resolve detail in the object that is being imaged, named by resolution, is the core parameter of an imaging system. Super-resolution is a class of techniques that can enhance the resolution of an imaging system and even…

Data Structures and Algorithms · Computer Science 2022-10-13 Yaonan Jin , Daogao Liu , Zhao Song

In this work, we present the \emph{twiddless fast Fourier transform (TFFT)}, a novel algorithm for computing the $N$-point discrete Fourier transform (DFT). The TFFT's divide strategy builds on recent results that decimate an $N$-point…

Computational Complexity · Computer Science 2025-12-23 Saulo Queiroz

t is a known fact that near field diffraction or Fresnel diffraction calculations are difficult to perform exactly. It is in general necessary to make some approximations in order to obtain a more suitable form. In this work, a numerical…

The computational efficiency of many neural operators, widely used for learning solutions of PDEs, relies on the fast Fourier transform (FFT) for performing spectral computations. As the FFT is limited to equispaced (rectangular) grids,…

Given a time series vector, how can we efficiently compute a specified part of Fourier coefficients? Fast Fourier transform (FFT) is a widely used algorithm that computes the discrete Fourier transform in many machine learning applications.…

Machine Learning · Computer Science 2020-08-31 Yong-chan Park , Jun-Gi Jang , U Kang

The graph fractional Fourier transform (GFRFT) for unitary graph Fourier transform (GFT) matrices can be interpreted through the scalar function $e^{j\alpha\theta}$ on the unit circle. Under the principal branch, its Fourier-series…

Signal Processing · Electrical Eng. & Systems 2026-05-19 Ziqi Yan , Mingzhi Wang , Sen Shi , Feiyue Zhao , Manjun Cui , Yangfan He , Zhichao Zhang

Non-line-of-Sight (NLOS) imaging systems collect light at a diffuse relay surface and input this measurement into computational algorithms that output a 3D volumetric reconstruction. These algorithms utilize the Fast Fourier Transform (FFT)…

Image and Video Processing · Electrical Eng. & Systems 2025-01-14 Talha Sultan , Alex Bocchieri , Chaoying Gu , Xiaochun Liu , Pavel Polynkin , Andreas Velten

Many interesting and fundamentally practical optimization problems, ranging from optics, to signal processing, to radar and acoustics, involve constraints on the Fourier transform of a function. It is well-known that the {\em fast Fourier…

Optimization and Control · Mathematics 2012-09-05 Robert J. Vanderbei

A new transform over finite fields, the finite field Hartley transform (FFHT), was recently introduced and a number of promising applications on the design of efficient multiple access systems and multilevel spread spectrum sequences were…

Numerical Analysis · Computer Science 2015-02-06 H. M. de Oliveira , R. G. F. Távora , R. J. Cintra , R. M. Campello de Souza

Achieving high spatial resolution is the goal of many imaging systems. Designing a high-resolution lens with diffraction-limited performance over a large field of view remains a difficult task in imaging system design. On the other hand,…