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Related papers: Phase Retrieval Problem. Application to VLBI Mappi…

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In order to produce high dynamic range images in radio interferometry, bright extended sources need to be removed with minimal error. However, this is not a trivial task because the Fourier plane is sampled only at a finite number of…

Instrumentation and Methods for Astrophysics · Physics 2011-01-17 Sarod Yatawatta

Phase retrieval is the nonlinear inverse problem of recovering a true signal from its Fourier magnitude measurements. It arises in many applications such as astronomical imaging, X-Ray crystallography, microscopy, and more. The problem is…

Computer Vision and Pattern Recognition · Computer Science 2023-05-11 Rohun Agrawal , Oscar Leong

This paper presents a simple method to recover phase information from regions of unresolvable fringe density, specifically, at the camera corners, where interference fringes are not resolved by the camera using Phase Shifting Interferometry…

Optics · Physics 2026-03-17 Indrani Bhattacharya

Recent years have witnessed rapid advancements in 3D scanning technologies, with applications spanning VR/AR, digital human creation, and medical imaging. Structured-light scanning with phase-shifting techniques is preferred for its use of…

Computer Vision and Pattern Recognition · Computer Science 2025-11-25 Xiang Gao , Xinmu Wang , Zhou Zhao , Junqi Huang , Xianfeng David Gu

In this paper I outline a new strategy for the routine detection and imaging of faint (sub-mJy and microJy) radio sources with VLBI and SVLBI. The strategy relies on a combination of in-beam phase-referencing, wide-field VLBI imaging and…

Astrophysics · Physics 2007-05-23 M. A. Garrett

We propose a new algorithm to learn a dictionary for reconstructing and sparsely encoding signals from measurements without phase. Specifically, we consider the task of estimating a two-dimensional image from squared-magnitude measurements…

Optimization and Control · Mathematics 2016-11-23 Andreas M. Tillmann , Yonina C. Eldar , Julien Mairal

Quantitative phase imaging (QPI) is a label-free technique providing both morphology and quantitative biophysical information in biomedicine. However, applying such a powerful technique to in vivo pathological diagnosis remains challenging.…

The direct observation of extrasolar planets and their spectra is coming into reach with the new generation of ground-based near-IR interferometers, like the Very Large Telescope Interferometer (VLTI). The high contrast between star and…

Astrophysics · Physics 2007-05-23 Viki Joergens , Andreas Quirrenbach

This paper focuses on phase retrieval from phaseless total-field data in biharmonic scattering problems. We prove that a phased biharmonic wave can be uniquely determined by the modulus of the total biharmonic wave within a nonempty domain.…

Analysis of PDEs · Mathematics 2026-02-16 Yuxiang Cheng , Xiaoxu Xu

The ultra-long wavelength sky ($\nu\lesssim 30$ MHz) is still largely unexplored, as the electromagnetic wave is heavily absorbed and distorted by the ionosphere on Earth. The far-side of the Moon, either in lunar-orbit or on lunar-surface,…

Astrophysics of Galaxies · Physics 2025-11-04 Qige Ao , Furen Deng , Yidong Xu , Bin Yue , Huanyuan Shan , Xuelei Chen

A method is described for the reconstruction of the amplitude and phase of the object exit wave function by phase-plate transmission electron microscopy. The proposed method can be considered as in-line holography and requires three images,…

Materials Science · Physics 2017-05-24 B. Gamm , M. Dries , K. Schultheiss , H. Blank , A. Rosenauer , R. R. Schröder , D. Gerthsen

High-throughput computational imaging requires efficient processing algorithms to retrieve multi-dimensional and multi-scale information. In computational phase imaging, phase retrieval (PR) is required to reconstruct both amplitude and…

Image and Video Processing · Electrical Eng. & Systems 2021-09-15 Xuyang Chang , Liheng Bian , Jun Zhang

In this work we develop an algorithm for signal reconstruction from the magnitude of its Fourier transform in a situation where some (non-zero) parts of the sought signal are known. Although our method does not assume that the known part…

Optics · Physics 2012-03-06 Eliyahu Osherovich , Michael Zibulevsky , Irad Yavneh

This paper proposes a novel structure-aware matrix completion framework assisted by radial basis function (RBF) interpolation for near-field radio map construction in extremely large multiple-input multiple-output (XL-MIMO) systems. Unlike…

Signal Processing · Electrical Eng. & Systems 2025-11-11 Hao Sun , Xianghao Yu , Junting Chen

Determining the phase of a wave from intensity measurements has many applications in fields such as electron microscopy, visible light optics, and medical imaging. Propagation based phase retrieval, where the phase is obtained from…

Image and Video Processing · Electrical Eng. & Systems 2018-04-10 Zachary David Cleary Kemp

Phase retrieval aims to recover a signal from magnitude or power spectra measurements. It is often addressed by considering a minimization problem involving a quadratic cost function. We propose a different formulation based on Bregman…

Sound · Computer Science 2020-12-01 Pierre-Hugo Vial , Paul Magron , Thomas Oberlin , Cédric Févotte

One of the hallmarks of active galactic nuclei are that they are highly variable with time. In watching the spectra vary it has been observed that the emission-lines often appear to "reverberate" -- that is they vary in response to…

Astrophysics of Galaxies · Physics 2026-05-28 Kirk Long , Keith Horne , Jason Dexter , Benoit Tremblay

Context: Phase referencing is a standard calibration technique in radio interferometry, particularly suited for the detection of weak sources close to the sensitivity limits of the interferometers. However, effects from a changing…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 I. Marti-Vidal , E. Ros , M. A. Perez Torres , J. C. Guirado , S. Jimenez-Monferrer , J. M. Marcaide

Audio super-resolution is a challenging task of recovering the missing high-resolution features from a low-resolution signal. To address this, generative adversarial networks (GAN) have been used to achieve promising results by training the…

Audio and Speech Processing · Electrical Eng. & Systems 2020-10-12 Shichao Hu , Bin Zhang , Beici Liang , Ethan Zhao , Simon Lui

A new multi-frequency synthesis algorithm for reconstructing images from multi-frequency VLBI data is proposed. The algorithm is based on a generalized maximum-entropy method, and makes it possible to derive an effective spectral correction…

Astrophysics · Physics 2011-08-31 Anisa T. Bajkova