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Velocity estimation is a cornerstone of the recently introduced near-field predictive beamforming. This paper derives the Cramer-Rao bounds (CRBs) for joint radial and transverse velocity estimation within a predictive beamforming framework…

Signal Processing · Electrical Eng. & Systems 2026-05-19 Khalid A. Alshumayri , Mudassir Masood , Ali. A. Nasir

We characterize the performance of the widely-used least-squares estimator in astrometry in terms of a comparison with the Cramer-Rao lower variance bound. In this inference context the performance of the least-squares estimator does not…

Instrumentation and Methods for Astrophysics · Physics 2015-11-18 Rodrigo A. Lobos , Jorge F. Silva , Rene A. Mendez , Marcos Orchard

We show that the quantum Cram\'er-Rao bound on the precision of measurements of the optical phase gradient, or the wavefront tilt, with a beam of finite width is consistent with the Heisenberg uncertainty principle for a single-photon…

Quantum Physics · Physics 2020-07-22 Walker Larson , Bahaa E. A. Saleh

Published analyses of very long baseline interferometry (VLBI) data for the sources included in the third International Celestial Reference Frame (ICRF3) catalog have revealed object-specific, excess astrometric variability and…

Astrophysics of Galaxies · Physics 2024-11-27 Valeri V. Makarov , Phil Cigan , David Gordon , Megan C. Johnson , Christopher DiLullo , Sébastien Lambert

Using five independent analytic and Monte Carlo simulation codes, we have studied the performance of wide field ground layer adaptive optics (GLAO), which can use a single, relatively low order deformable mirror to correct the wavefront…

Following previous suggestions of other researchers, this paper discusses the prospects for astrometric observation of MACHO gravitational microlensing events. We derive the expected astrometric observables for a simple microlensing event…

Astrophysics · Physics 2009-10-30 A. F. Boden , M. Shao , D. Van Buren

We present the third installment of the Yale/San Juan Southern Proper Motion Catalog, SPM3. Absolute proper motions, positions, and photographic B,V photometry are given for roughly 10.7 million objects, primarily stars, down to a magnitude…

Astrophysics · Physics 2009-11-10 T. M. Girard , D. I. Dinescu , W. F. van Altena , I. Platais , D. G. Monet , C. E. Lopez

Adaptive optic (AO) systems delivering high levels of wavefront correction are now common at observatories. One of the main limitations to image quality after wavefront correction comes from atmospheric refraction. An Atmospheric dispersion…

Instrumentation and Methods for Astrophysics · Physics 2018-01-31 Prashant Pathak , Olivier Guyon , Nemanja Jovanovic , Julien Lozi , Frantz Martinache , Yosuke Minowa , Tomoyuki Kudo , Takayuki Kotani , Hideki Takami

We present novel lower bounds on the localization error using a network of satellites randomly deployed on a sphere around Earth. Our new analysis approach characterizes the localization performance by its asymptotic behavior as the number…

Signal Processing · Electrical Eng. & Systems 2022-06-08 Hodaya Halevi , Itsik Bergel , Yair Noam

Extremely precise radial velocity is essential for the detection of sub-m/s radial velocity of stars induced by Earth-like planets. Although modeling of the barycentric correction of radial velocity could achieve 1 mm/s precision, the input…

Earth and Planetary Astrophysics · Physics 2023-12-13 Yicheng Rui , Fabo Feng

We investigate properties of astrometric microlensing of distant sources (such as QSOs and radio galaxies) caused by stars in the Galaxy, mainly focusing on application to the VERA (VLBI Exploration of Radio Astrometry) project. Assuming…

Astrophysics · Physics 2009-11-07 Mareki Honma , Tomoharu Kurayama

This letter addresses the detection problem of dim maneuvering targets in the presence of range cell migration. Specifically, it is assumed that the moving target can appear in more than one range cell within the transmitted pulse train.…

Signal Processing · Electrical Eng. & Systems 2021-05-05 Sheng Yan , Pia Addabbo , Chengpeng Hao , Danilo Orlando

The Breakthrough Starshot project aims to send centimeter-sized, gram-scale "StarChip" probes to Alpha Centauri at a speed of $\sim0.2c$. On the other hand, Zhang \& Li recently proposed that trans-relativistic cameras may be sent to any…

High Energy Astrophysical Phenomena · Physics 2019-05-28 Jin-Ping Zhu , Bing Zhang , Yuan-Pei Yang

Spectral Estimation (SpecEst) is a core area of signal processing with a history spanning two centuries and applications across various fields. With the advent of digital acquisition, SpecEst algorithms have been widely applied to tasks…

Signal Processing · Electrical Eng. & Systems 2025-05-07 Ruiming Guo , Ayush Bhandari

The Space Interferometry Mission (SIM), with its launch date planned for 2005, has as its goal astrometry with ~ 1 micro-arcsecond accuracy for stars as faint as 20th mag. If the SIM lives to expectations it can be used to measure…

Astrophysics · Physics 2009-10-30 Bohdan Paczynski

The cross-identification of sources in separate catalogs is one of the most basic tasks in observational astronomy. It is, however, surprisingly difficult and generally ill-defined. Recently Budav\'ari & Szalay (2008) formulated the problem…

Astrophysics of Galaxies · Physics 2015-05-19 Gyöngyi Kerekes , Tamás Budavári , István Csabai , Andrew J. Connolly , Alexander S. Szalay

As astronomical photometric surveys continue to tile the sky repeatedly, the potential to pushdetection thresholds to fainter limits increases; however, traditional digital-tracking methods cannotachieve this efficiently beyond time scales…

Earth and Planetary Astrophysics · Physics 2021-04-09 Nathan Golovich , Noah Lifset , Robert Armstrong , Eric Green , Michael D. Schneider , Roger Pearce

Mobility entropy is proposed to measure predictability of human movements, based on which, the upper and lower bound of prediction accuracy is deduced, but corresponding mathematical expressions of prediction accuracy keeps yet open. In…

Social and Information Networks · Computer Science 2019-01-29 Lu Liu , Wuyang Zhou , Sihai Zhang , Wei Cai

With the aim of paving the road for future accurate astrometry with MICADO at the European-ELT, we performed an astrometric study using two different but complementary approaches to investigate two critical components that contribute to the…

Radio emission propagating over an Earth-pulsar line of sight provides a unique probe of the intervening ionized interstellar medium (ISM). Variations in the integrated electron column density along this line of sight, or dispersion measure…

High Energy Astrophysical Phenomena · Physics 2020-04-08 M. T. Lam , T. J. W. Lazio , T. Dolch , M. L. Jones , M. A. McLaughlin , D. R. Stinebring , M. Surnis
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