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I propose a superoscillation measurement method for subdiffraction incoherent optical sources, with potential applications in astronomy, remote sensing, fluorescence microscopy, and spectroscopy. The proposal, based on coherent optical…

Quantum Physics · Physics 2022-10-10 Mankei Tsang

We present a new blind formulation of the Cosmic Microwave Background (CMB) inference problem. The approach relies on a phenomenological model of the multi-frequency microwave sky without the need for physical models of the individual…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-30 Flavien Vansyngel , Benjamin D. Wandelt , Jean-François Cardoso , Karim Benabed

Ground-based observation at frequencies below 30 MHz is hindered by the ionosphere of the Earth and radio frequency interference. To map the sky at these low frequencies, we have proposed the Discovering the Sky at the Longest wavelength…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 Yuan Shi , Yidong Xu , Li Deng , Fengquan Wu , Lin Wu , Qizhi Huang , Shifan Zuo , Jingye Yan , Xuelei Chen

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

Measuring neutron star radii with spectroscopic and timing techniques relies on the combination of multiple observables to break the degeneracies between the mass and radius introduced by general relativistic effects. Here, we explore a…

High Energy Astrophysical Phenomena · Physics 2015-10-21 Feryal Ozel , Dimitrios Psaltis

In this paper, we apply a new statistical analysis technique, Mean Field approach to Bayesian Independent Component Analysis (MF-ICA), on galaxy spectral analysis. This algorithm can compress the stellar spectral library into a few…

Astrophysics of Galaxies · Physics 2016-03-16 Ning Hu , Shan-Shan Su , Xu Kong

This study puts forward a generalization of the short-time Fourier-based Synchrosqueezing Transform using a new local estimate of instantaneous frequency. Such a technique enables not only to achieve a highly concentrated time-frequency…

Signal Processing · Electrical Eng. & Systems 2020-04-21 Duong-Hung Pham , Sylvain Meignen

Diffraction limit is manifested in the loss of high spatial frequency information that results from decay of evanescent waves. As a result, conventional far-field optics yields no information about an object's subwavelength features. Here…

Optics · Physics 2012-01-24 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

We propose a new, efficient multi-scale method to decompose a map (or signal in general) into components maps that contain structures of different sizes. In the widely-used wave transform, artifacts containing negative values arise around…

Instrumentation and Methods for Astrophysics · Physics 2022-04-11 Guang-Xing Li

We propose an illumination strategy for interferometric imaging that allows for robust depth recovery from intensity-only measurements. For an array with colocated sources and receivers, we show that all the possible interferometric data…

Optimization and Control · Mathematics 2016-11-30 Miguel Moscoso , Alexei Novikov , George Papanicolaou , Chrysoula Tsogka

Radio-astronomical observations are increasingly corrupted by RF interference, and online detection and filtering algorithms are becoming essential. To facilitate the introduction of such techniques into radio astronomy, we formulate the…

Astrophysics · Physics 2009-10-31 Amir Leshem , Alle-Jan van der Veen , Albert-Jan Boonstra

Since its formulation by Hamaker et al., the radio interferometer measurement equation (RIME) has provided a rigorous mathematical basis for the development of novel calibration methods and techniques, including various approaches to the…

Instrumentation and Methods for Astrophysics · Physics 2011-02-07 Oleg M. Smirnov

The current status of the high spatial resolution imaging interferometry in optical astronomy is reviewed in the light of theoretical explanation, as well as of experimental constraints that exist in the present day technology. The basic…

Astrophysics · Physics 2007-05-23 S. K. Saha

We present a fast Bayesian inference framework to address the growing computational cost of gravitational-wave parameter estimation. The increased cost is driven by improved broadband detector sensitivity, particularly at low frequencies…

General Relativity and Quantum Cosmology · Physics 2025-08-07 Abhishek Sharma , Lalit Pathak , Soumen Roy , Anand S. Sengupta

Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

Most satellites decouple the acquisition of a panchromatic image at high spatial resolution from the acquisition of a multispectral image at lower spatial resolution. Pansharpening is a fusion technique used to increase the spatial…

Computer Vision and Pattern Recognition · Computer Science 2017-08-08 Joan Duran , Antoni Buades , Bartomeu Coll , Catalina Sbert , Gwendoline Blanchet

Spectrum sensing is an essential enabling functionality for cognitive radio networks to detect spectrum holes and opportunistically use the under-utilized frequency bands without causing harmful interference to legacy networks. This paper…

Information Theory · Computer Science 2016-11-18 Zhi Quan , Shuguang Cui , Ali H. Sayed , H. Vincent Poor

Spatial resolution of most imaging devices is fundamentally restricted by diffraction. This limitation is manifested in the loss of high spatial frequency information contained in evanescent waves. As a result, conventional far-field optics…

Optics · Physics 2010-03-16 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

Line-intensity mapping (LIM) is an emerging cosmological technique that traces large-scale structure through the integrated spectral-line emission of unresolved sources. Reconstructing unbiased sky maps requires careful joint treatment of…

Instrumentation and Methods for Astrophysics · Physics 2026-03-25 Zheng Zhang , Philip Bull , Mario G. Santos , Ainulnabilah Nasirudin

A general-purpose all-fiber spectrometer is demonstrated to overcome the trade-off between spectral resolution and bandwidth. By integrating a wavelength division multiplexer with five multimode optical fibers, we have achieved 100 nm…

Instrumentation and Detectors · Physics 2016-08-26 Seng Fatt Liew , Brandon Redding , Michael A. Choma , Hemant D. Tagare , Hui Cao