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Interferometric phase measurement is widely used to precisely determine quantities such as length, speed, and material properties. Without quantum correlations, the best phase sensitivity $\Delta\varphi$ achievable using $n$ photons is the…

This paper presents key performance metrics for near-field communication and sensing systems and their scaling behavior as a function of the antenna array aperture. Analytical expressions are derived for several standard array geometries to…

Signal Processing · Electrical Eng. & Systems 2026-01-09 Marcin Wachowiak , André Bourdoux , Sofie Pollin

The high demand for 3D imaging in intelligent robotics is motivating the advances of coherent LiDARs towards high performances with low complexity/cost. However, the current coherent LiDARs suffer from the tight coupling between the high…

Optics · Physics 2024-12-31 Long Wang , Liang Hu , Wenhai Jiao , Yaxin Shang , Jianping Chen , Guiling Wu

Millimetre-VLBI is an important tool in AGN astrophysics, but it is limited by short atmospheric coherence times and poor receiver and antenna performance. We demonstrate a new kind of phase referencing for the VLBA, enabling us to increase…

Astrophysics · Physics 2007-05-23 E. Middelberg , A. L. Roy , R. C. Walker , H. Falcke , T. P. Krichbaum

Radio interferometric imaging aims to estimate an unknown sky intensity image from degraded observations, acquired through an antenna array. In the theoretical case of a perfectly calibrated array, it has been shown that solving the…

Instrumentation and Methods for Astrophysics · Physics 2017-07-25 Audrey Repetti , Jasleen Birdi , Arwa Dabbech , Yves Wiaux

Free electrons in the interstellar medium cause frequency-dependent delays in pulse arrival times due to both scattering and dispersion. Multi-frequency measurements are used to estimate and remove dispersion delays. In this paper, we focus…

High Energy Astrophysical Phenomena · Physics 2015-06-23 M. T. Lam , J. M. Cordes , S. Chatterjee , T. Dolch

Inertia amplification is a mechanism coupling degrees of freedom within a vibrating structure. Its goal is to achieve an apparent high dynamic mass and, accordingly, a low resonance frequency. Such structures have been described for use in…

Interferometric imaging now achieves angular resolutions as fine as 10 microarcsec, probing scales that are inaccessible to single telescopes. Traditional synthesis imaging methods require calibrated visibilities; however, interferometric…

Instrumentation and Methods for Astrophysics · Physics 2018-04-25 Andrew A. Chael , Michael D. Johnson , Katherine L. Bouman , Lindy L. Blackburn , Kazunori Akiyama , Ramesh Narayan

The ngVLA will enable significant advances in our understanding of the formation and evolution of multiple star systems in the protostellar phase, building upon the breakthroughs enabled by the VLA. The high-sensitivity and resolution at…

Astrophysics of Galaxies · Physics 2018-10-17 John Tobin , Patrick Sheehan , Doug Johnstone

Antenna array calibration is necessary to maintain the high fidelity of beam patterns across a wide range of advanced antenna systems and to ensure channel reciprocity in time division duplexing schemes. Despite the continuous development…

Signal Processing · Electrical Eng. & Systems 2023-05-26 Sergey S. Tambovskiy , Gábor Fodor , Hugo M. Tullberg

Most use cases of reconfigurable antennas require an accurate forward model mapping configuration to radiated field (and reflections at feeds). Emerging dynamic metasurface antennas (DMAs) confront the conventional approach of extracting…

Applied Physics · Physics 2025-12-30 Jean Tapie , Philipp del Hougne

The Atacama Large millimetre/submillimetre Array (ALMA) makes use of water vapour radiometers (WVR), which monitor the atmospheric water vapour line at 183 GHz along the line of sight above each antenna to correct for phase delays…

Instrumentation and Methods for Astrophysics · Physics 2017-09-20 L. T. Maud , R. P. J. Tilanus , T. A. van Kempen , M. R. Hogerheijde , M. Schmalzl , I. Yoon , Y. Contreras , M. C. Toribio , Y. Asaki , W. R. F. Dent , E. Fomalont , S. Matsushita

Achromatic combinations of a diffractive Phase Fresnel Lens and a refractive correcting element have been proposed for X-ray and gamma-ray astronomy and for microlithography, but considerations of absorption often dictate that the…

Astrophysics · Physics 2009-11-10 Gerald K. Skinner

Maintaining natural image statistics is a crucial factor in restoration and generation of realistic looking images. When training CNNs, photorealism is usually attempted by adversarial training (GAN), that pushes the output images to lie on…

Computer Vision and Pattern Recognition · Computer Science 2018-07-19 Roey Mechrez , Itamar Talmi , Firas Shama , Lihi Zelnik-Manor

Optical sensing schemes that rely on two-photon interference provide a powerful platform for precision metrology, although they are inherently constrained by a trade-off between dynamic range and measurement precision. To overcome this…

Autonomous underwater vehicles (AUV) are commonly used in many underwater applications. Recently, the usage of multi-rotor unmanned autonomous vehicles (UAV) for marine applications is receiving more attention in the literature. Usually,…

Robotics · Computer Science 2022-08-18 Barak Or , Itzik Klein

The redshifted 21 cm brightness distribution from neutral hydrogen is a promising probe into the cosmic dark ages, cosmic dawn, and re-ionization. LOFAR's Low Band Antennas (LBA) may be used in the frequency range 45 MHz to 85 MHz (30>z>16)…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 H. K. Vedantham , L. V. E. Koopmans , A. G. de Bruyn , S. J. Wijnholds , B. Ciardi , M. A. Brentjens

Novel view synthesis (NVS) is a challenging task in computer vision that involves synthesizing new views of a scene from a limited set of input images. Neural Radiance Fields (NeRF) have emerged as a powerful approach to address this…

Computer Vision and Pattern Recognition · Computer Science 2023-03-16 Shuja Khalid , Frank Rudzicz

Multiple wavelength phase shifting interferometry is widely used to extend the unambiguous range (UR) beyond that of a single wavelength. Towards this end, many algorithms have been developed to calculate the optical path difference (OPD)…

Optics · Physics 2023-09-20 Robert H. Leonard , Spencer E. Olson

Observations made with the VLBA have led to fundamental advances in our understanding of how radio jets in AGN evolve from parsec-scales out to distances exceeding several hundred kiloparsecs. In this review I discuss current models of…

Astrophysics · Physics 2007-07-12 Matthew L. Lister