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Related papers: Simulations of astronomical imaging phased arrays

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Optical phase-space functions describe spatial and angular information simultaneously; examples include light fields in ray optics and Wigner functions in wave optics. Measurement of phase-space enables digital refocusing, aberration…

Optics · Physics 2017-08-02 Hsiou-Yuan Liu , Jingshan Zhong , Laura Waller

In close binary systems the atmosphere of one or both components can be significantly influenced by irradiation from the companion. Often the irradiated atmosphere is simulated with a single-temperature approximation for the entire…

Solar and Stellar Astrophysics · Physics 2015-03-17 H. M. Guenther , A. C. Wawrzyn

In this paper, as opposed to the random phase masks, the structured illuminations with a pixel-dependent deterministic phase shift are considered to derandomize the model setup. The RAAR algorithm is modified to adapt to two or more…

Numerical Analysis · Mathematics 2017-02-01 Ji Li , Tie Zhou

The accumulation of aberrations along the optical path in a telescope produces distortions and speckles in the resulting images, limiting the performance of cameras at high angular resolution. It is important to achieve the highest possible…

Instrumentation and Methods for Astrophysics · Physics 2021-03-17 Benjamin J. S. Pope , Laurent Pueyo , Yinzi Xin , Peter G. Tuthill

We consider an error model for phased array with gain errors and phase errors, with errors dependent on the phase applied and the antenna index. Under this model, we propose an algorithm for measuring the errors by selectively turning on…

Signal Processing · Electrical Eng. & Systems 2021-07-21 Joyson Sebastian , Pranav Dayal , Kee-Bong Song , Walid AliAhmad

We developed analytical technique for extracting the phase, visibility and amplitude information as needed for interferometric astrometry with the Space Interferometry Mission (SIM). Our model accounts for a number of physical and…

Optics · Physics 2008-11-26 Slava G. Turyshev

The optimal instant of observation of astrophysical phenomena for objects that vary on human time-sales is an important problem, as it bears on the cost-effective use of usually scarce observational facilities. In this paper we address this…

Solar and Stellar Astrophysics · Physics 2023-02-15 Miguel Videla , Rene A. Mendez , Jorge F. Silva , Marcos E. Orchard

Context. Multi-element phased-array radio telescopes use digital beamforming to widen their field-of-view with numerous tied-array beams (TABs). These beams share bandpass variations and radio frequency interference (RFI). Yet, most pulsar…

Instrumentation and Methods for Astrophysics · Physics 2026-03-16 Dirk Kuiper , Cees Bassa , Ziggy Pleunis , Jason Hessels

The optical properties of sub-wavelength arrays of atoms or other quantum emitters have attracted significant interest recently. For example, the strong constructive or destructive interference of emitted light enables arrays to function as…

Quantum Physics · Physics 2019-12-20 A. Asenjo-Garcia , H. J. Kimble , D. E. Chang

We present the method of multiplexed imaging designed for astronomical observations of large sky areas in the IR, visible and UV frequencies. Our method relies on the sparse nature of astronomical observations. The method consists of an…

Instrumentation and Methods for Astrophysics · Physics 2014-03-11 Barak Zackay , Avishay Gal-Yam

We present a novel method to significantly speed up cosmological parameter sampling. The method relies on constructing an interpolation of the CMB-log-likelihood based on sparse grids, which is used as a shortcut for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Mona Frommert , Dirk Pflueger , Thomas Riller , Martin Reinecke , Hans-Joachim Bungartz , Torsten Ensslin

The time-modulated array (TMA) is a simple array architecture in which each antenna is connected via a multi-throw switch. The switch acts as a modulator switching state faster than the symbol rate. The phase shifting and beamforming is…

Signal Processing · Electrical Eng. & Systems 2025-02-13 Marcin Wachowiak , André Bourdoux , Sofie Pollin

We demonstrate a different scheme to perform optical sectioning of a sample based on the concept of induced coherence [Zou et al., Phys. Rev. Lett. 67, 318 (1991)]. This can be viewed as a different type of optical coherence tomography…

Quantum Physics · Physics 2018-02-19 Adam Vallés , Gerard Jiménez , Luis José Salazar-Serrano , Juan P. Torres

A new method for improving the resolution of astronomical images is presented. It is based on the principle that sampled data cannot be fully deconvolved without violating the sampling theorem. Thus, the sampled image should not be…

Astrophysics · Physics 2009-10-30 P. Magain , F. Courbin , S. Sohy

Complementarity is usually considered as a phenomenon of microscopic systems. In this paper we report an experimental observation of complementarity in the correlated double-slit interference with a pseudothermal light source. The thermal…

Quantum Physics · Physics 2007-05-23 De-Zhong Cao , Jun Xiong , Hua Tang , Lu-Fang Lin , Su-Heng Zhang , Kaige Wang

By observing bright and compact astronomical sources while also taking data with the 183 GHz Water Vapour Radiometers, ALMA will be able to measure the `empirical' relationship between fluctuations in the phase of the astronomical signal…

Instrumentation and Methods for Astrophysics · Physics 2009-07-28 Bojan Nikolic

Ptychography promises diffraction limited resolution without the need for high resolution lenses. To achieve high resolution one has to solve the phase problem for many partially overlapping frames. Here we review some of the existing…

Optics · Physics 2012-09-24 C. Yang , J. Qian , A. Schirotzek , F. Maia , S. Marchesini

Ellipsometry is a powerful and well-established optical technique used in the characterisation of materials. It works by combining the components of elliptically polarized light in order to draw information about the optical system. We…

Optics · Physics 2018-03-15 Manoel P. Araújo , Stefano De Leo , Gabriel G. Maia

3D image reconstruction from a set of X-ray projections is an important image reconstruction problem, with applications in medical imaging, industrial inspection and airport security. The innovation of X-ray emitter arrays allows for a…

Medical Physics · Physics 2016-11-23 Maria Klodt , Raphael Hauser

The advent of extremely large telescopes will bring unprecedented light-collecting power and spatial resolution, but it will also lead to a significant increase in the size and complexity of focal-plane instruments. The use of freeform…

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