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In this letter, a fast Fourier transform (FFT)-enhanced low-complexity super-resolution sensing algorithm for near-field source localization with both angle and range estimation is proposed. Most traditional near-field source localization…

Signal Processing · Electrical Eng. & Systems 2024-11-26 Yuxiao Wu , Huizhi Wang , Yong Zeng

Extended source effects can be seen in gravitational lensing events when sources cross critical lines. Those events probe the stellar intensity profile and could be used to measure limb darkening coefficients to test stellar model…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Hans J. Witt , F. Atrio-Barandela

Recent advancements have illuminated the efficacy of some tensorization-decomposition Parameter-Efficient Fine-Tuning methods like LoRA and FacT in the context of Vision Transformers (ViT). However, these methods grapple with the challenges…

Computer Vision and Pattern Recognition · Computer Science 2023-11-14 Dongping Chen

To determine the magnification of an extended source caused by gravitational lensing one has to perform a two-dimensional integral over point-source magnifications in general. Since the point-source magnification jumps to an infinite value…

Astrophysics · Physics 2011-05-23 M. Dominik

A mixed precision Fast Fourier transform (FFT) implementation is presented. The procedure uses per-block microscaling (MX), a global power-of-two prescale, and prequantized low bit twiddles. We evaluate forward and round-trip FFT fidelity…

Signal Processing · Electrical Eng. & Systems 2026-02-18 Nikhil Deveshwar , Abhejit Rajagopal , Peder E. Z. Larson

We describe an update to the Herschel-SPIRE Fourier-Transform Spectrometer (FTS) calibration for extended sources, which incorporates a correction for the frequency-dependent far-field feedhorn efficiency, $\eta_\mathrm{FF}$. This…

Gravitational waves (GWs) exhibit wave-optics effects when their wavelength is comparable to the scale of the gravitational lens. This may occur in lensing from galactic subhalos in GWs emitted by binary black-hole mergers, and is gaining…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-16 Nino Ephremidze , Marc Kamionkowski , Cora Dvorkin

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

The goal of this paper is to provide a numerically fast and stable description for the microlensing amplification of an extended source (either uniform or limb-darkened) that holds in any amplification regime. We show that our method of…

Astrophysics of Galaxies · Physics 2011-02-11 C. -H. Lee , A. Riffeser , S. Seitz , R. Bender

This paper presents a new approach on stretch processing for a fine range estimation using MPM (Matrix Pencil Method). The conventional method utilizes FFT (Fast Fourier Transform) with limited range resolution with its fixed number of…

Computational Physics · Physics 2012-09-12 Minwook Kwon , Zhou Du , Jinwook Kim , Mingyu Yoon , Jinhwan Koh

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

The technologically-relevant task of feature extraction from data performed in deep-learning systems is routinely accomplished as repeated fast Fourier transforms (FFT) electronically in prevalent domain-specific architectures such as in…

This summary of the doctoral thesis provides a comprehensive formulation of the Extended Discrete Fourier Transform (EDFT), derived directly from the Fourier integral and its orthogonality properties. The method is obtained by solving…

Data Structures and Algorithms · Computer Science 2026-01-21 Vilnis Liepins

This paper is to investigate the high-quality analytical reconstructions of multiple source-translation computed tomography (mSTCT) under an extended field of view (FOV). Under the larger FOVs, the previously proposed backprojection…

Computer Vision and Pattern Recognition · Computer Science 2023-07-13 Zhisheng Wang , Yue Liu , Shunli Wang , Xingyuan Bian , Zongfeng Li , Junning Cui

Inverse path tracing has recently been applied to joint material and lighting estimation, given geometry and multi-view HDR observations of an indoor scene. However, it has two major limitations: path tracing is expensive to compute, and…

Computer Vision and Pattern Recognition · Computer Science 2023-08-25 Liwen Wu , Rui Zhu , Mustafa B. Yaldiz , Yinhao Zhu , Hong Cai , Janarbek Matai , Fatih Porikli , Tzu-Mao Li , Manmohan Chandraker , Ravi Ramamoorthi

Fourier ptychographic microscopy enables gigapixel-scale imaging, with both large field-of-view and high resolution. Using a set of low-resolution images that are recorded under varying illumination angles, the goal is to computationally…

Signal Processing · Electrical Eng. & Systems 2018-03-13 Emrah Bostan , Mahdi Soltanolkotabi , David Ren , Laura Waller

We consider finite approximations of a fractal generated by an iterated function system of affine transformations on $\mathbb{R}^d$ as a discrete set of data points. Considering a signal supported on this finite approximation, we propose a…

Functional Analysis · Mathematics 2016-07-14 Calvin Hotchkiss , Eric S. Weber

Numerical simulation of Fresnel diffraction with fast Fourier transform (FFT) is widely used in optics, especially computer holography. Fresnel diffraction with FFT cannot set different sampling rates between source and destination planes,…

We consider the Fast Fourier Transform (FFT) based numerical method for thin film magnetization problems [Vestg{\aa}rden and Johansen, SuST, 25 (2012) 104001], compare it with the finite element methods, and evaluate its accuracy. Proposed…

Computational Physics · Physics 2018-05-09 Leonid Prigozhin , Vladimir Sokolovsky

Correlations in the Lyman-$\alpha$ (Ly$\alpha$) forest, both as a function of line of sight separation (1D) and 3D separation, provide a unique window to the distribution of matter at redshifts not accessible by current galaxy surveys.…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-07 Martine Lokken , Andreu Font-Ribera , Patrick McDonald
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