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Heterodyne interferometry for precision science often comes with an optical phase modulation, for example, for intersatellite clock noise transfer for gravitational wave (GW) detectors in space, exemplified by the Laser Interferometer Space…

Instrumentation and Methods for Astrophysics · Physics 2025-12-22 Kohei Yamamoto , Olaf Hartwig , Lennart Wissel , Holly Leopardi , Kenji Numata , Ryan Derosa

We demonstrate accurate phase measurement from low photon level interference data using a constrained optimization method that takes into account the expected redundancy in the unknown phase function. This approach is shown to have…

Quantum Physics · Physics 2015-06-23 Mandeep Singh , Kedar Khare , Anand Kumar Jha , Shashi Prabhakar , R. P. Singh

The accuracy of position measurements on stellar targets with the future Space Interferometry Mission (SIM) will be limited not only by photon noise and by the properties of the instrument (design, stability, etc.) and the overall…

Astrophysics · Physics 2009-11-13 R. Sridharan , Ronald J. Allen

We have assessed accuracy of estimates of Earth orientation parameters (EOP) determined from several very long baseline interferometry (VLBI) observing programs that ran concurrently at different networks. We consider that the root mean…

Geophysics · Physics 2026-03-09 Leonid Petrov , Christian Ploetz , Matthias Schartner

Beampattern synthesis seeks to optimize array weights to shape radiation patterns, playing a critical role in various wireless applications. In addition to theoretical advancements, recent hardware innovations have facilitated new avenues…

Signal Processing · Electrical Eng. & Systems 2025-03-07 Pinjun Zheng , Md. Jahangir Hossain , Anas Chaaban

Direction dependent calibration of widefield radio interferometers estimates the systematic errors along multiple directions in the sky. This is necessary because with most systematic errors that are caused by effects such as the ionosphere…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 Sarod Yatawatta

A first statistical detection of the 21-cm Epoch of Reionization (EoR) is on the horizon, as cosmological volumes of the Universe become accessible via the adoption of low-frequency interferometers. We explore the impact which non-identical…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 A. Chokshi , N. Barry , J. L. B. Line , C. H. Jordan , B. Pindor , R. L. Webster

Atmospheric propagation errors are a main constraint on the accuracy of Very Long Baseline Interferometry (VLBI) astrometry. For relative astrometry, differential techniques can mitigate these errors, but their effectiveness diminishes with…

Instrumentation and Methods for Astrophysics · Physics 2025-05-26 Jingdong Zhang , Bo Zhang , Shuangjing Xu , Maria J. Rioja , Richard Dodson , Xiaofeng Mai , Oleg Titov

Flattened and kinematically correlated planes of dwarf satellite galaxies have been observed in the Local Volume. The slinging out of satellites during host galaxy mergers has been suggested as a formation mechanism for these peculiar…

Astrophysics of Galaxies · Physics 2023-07-10 Kosuke Jamie Kanehisa , Marcel S. Pawlowski , Oliver Müller

Wide-field radio interferometric telescopes such as the Square Kilometre Array now being designed are subject to a number of aberrations. One particularly pernicious aberration is that due to non-coplanar baselines whereby long baselines…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 T. J. Cornwell , M. A. Voronkov , B. Humphreys

The ionosphere introduces chromatic distortions on low frequency radio waves, and thus poses a hurdle for 21-cm cosmology. In this paper we introduce time-varying chromatic ionospheric effects on simulated antenna temperature data of a…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Emma Shen , Dominic Anstey , Eloy de Lera Acedo , Anastasia Fialkov

Multi-photon interference results in modulations of output probabilities with phase shift periods that are much shorter than 2 Pi. Here, we investigate the physics behind these statistical patterns in the case of well-defined photon numbers…

Quantum Physics · Physics 2016-10-12 Holger F. Hofmann , Keito Hibino , Kazuya Fujiwara , Jun-Yi Wu

Measuring the phase of light is fundamental to optical imaging, sensing, and signal processing applications. Conventional optical phase measurements rely on multipath configurations, bulky interferometric setups, and computationally…

Phase retrieval problems in antenna measurements arise when a reference phase cannot be provided to all measurement locations. Phase retrieval algorithms require sufficiently many independent measurement samples of the radiated fields to be…

Signal Processing · Electrical Eng. & Systems 2022-06-24 Josef Knapp , Alexander Paulus , Jonas Kornprobst , Uwe Siart , Thomas F. Eibert

Generally, wave field reconstructions obtained by phase-retrieval algorithms are noisy, blurred and corrupted by various artifacts such as irregular waves, spots, etc. These disturbances, arising due to many factors such as non-idealities…

Optics · Physics 2012-07-24 Artem Migukin , Mostafa Agour , Vladimir Katkovnik

The incorporation of subarrays in Direct Radiating Arrays for satellite missions is fundamental in reducing the number of Radio Frequency chains, which correspondingly diminishes cost, power consumption, space, and mass. Despite the…

Radio Frequency Interference (RFI) is emitted from various sources, terrestrial or orbital, and create a nuisance for ground-based 21cm experiments. In particular, single-dish 21cm intensity mapping experiments will be highly susceptible to…

Interferometric Synthetic Aperture Radar (InSAR) Imaging methods are usually based on algorithms of match-filtering type, without considering the scene's characteristic, which causes limited imaging quality. Besides, post-processing steps…

Signal Processing · Electrical Eng. & Systems 2022-10-07 Xu Zhan , Xiaoling Zhang , Shunjun Wei , Jun Shi

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

The precise characterization and mitigation of systematic effects is one of the biggest roadblocks impeding the detection of the fluctuations of cosmological 21cm signals. Missing data in radio cosmological experiments, often due to radio…

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