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Related papers: Demonstration of Orbit Determination for LEO Objec…

200 papers

We present and evaluate several strategies to search for prompt, low-frequency radio emission associated with gravitational wave transients using the Murchison Widefield Array (MWA). As we are able to repoint the MWA on timescales of tens…

Instrumentation and Methods for Astrophysics · Physics 2016-10-12 D. L. Kaplan , T. Murphy , A. Rowlinson , S. D. Croft , R. B. Wayth , C. M. Trott

Low frequency imaging radio arrays such as MWA, LWA and LOFAR have been recently commissioned, and significantly more advanced and flexible arrays are planned for the near term. These powerful instruments offer new opportunities for direct…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 C. Lonsdale , L. Benkevitch , I. Cairns , M. Crowley , P. Erickson , M. Knapp , K. Kozarev , F. Lind , P. McCauley , J. Morgan , D. Oberoi

Detection of the fluctuations in 21 cm line emission from neutral hydrogen during the Epoch of Reionization in thousand hour integrations poses stringent requirements on calibration and image quality, both of which necessitate accurate…

Following the results of our previous low frequency searches for extraterrestrial intelligence (SETI) using the Murchison Widefield Array (MWA), directed toward the Galactic Centre and the Orion Molecular Cloud (Galactic Anticentre), we…

Instrumentation and Methods for Astrophysics · Physics 2020-09-08 Chenoa D. Tremblay , Steven J. Tingay

We present the first spectroscopic images of solar radio transients from the prototype for the Murchison Widefield Array (MWA), observed on 2010 March 27. Our observations span the instantaneous frequency band 170.9-201.6 MHz. Though our…

We have used an existing, robotic, multi-lens, all-sky camera system, coupled to a dedicated data reduction pipeline, to automatically determine orbital parameters of satellites in Low Earth Orbit (LEO). Each of the fixed cameras has a…

Instrumentation and Methods for Astrophysics · Physics 2020-04-20 T. P. G. Wijnen , R. Stuik , M. Rodenhuis , M. Langbroek , P. Wijnja

Low Earth orbit (LEO) satellites offer a promising alternative to global navigation satellite systems for precise positioning; however, their relatively low altitudes make them more susceptible to orbital perturbations, which in turn…

Signal Processing · Electrical Eng. & Systems 2025-11-11 Jie Ma , Pinjun Zheng , Xing Liu , Yuchen Zhang , Ali A. Nasir , Tareq Y. Al-Naffouri

We propose a method to account for the Earth oblateness effect in preliminary orbit determination of satellites in low orbits with radar observations. This method is an improvement of the one described in (Gronchi et al 2015), which uses a…

Space Physics · Physics 2018-10-24 Helene Ma , Giovanni F. Gronchi , Davide Bracali Cioci

We report the design and functionality of the Murchison Widefield Array Particle Detector Array (MWA PDA), an array of eight particle scintillation detectors deployed to Inyarrimanha Ilgari Bundara, the Murchison Radio-astronomy Observatory…

The Murchison Widefield Array (MWA) is an electronically steered low frequency ($<300$\,MHz) radio interferometer, with a `slew' time less than 8seconds. Low frequency ($\sim 100$\,MHz) radio telescopes are ideally suited for rapid-response…

We present a broadband map of polarized diffuse emission at 167-198 MHz developed from data from the Murchison Widefield Array (MWA). The map is designed to improve visibility simulation and precision calibration for 21 cm Epoch of…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-17 Ruby Byrne , Miguel F. Morales , Bryna Hazelton , Ian Sullivan , Nichole Barry , Christene Lynch , Jack L. B. Line , Daniel C. Jacobs

We present Murchison Widefield Array (MWA) monitoring of the Kepler K2 mission Fields 3, 4, and 5 at frequencies of 155 and 186 MHz, from observations contemporaneous with the K2 observations. This work follows from previous MWA and GMRT…

High Energy Astrophysical Phenomena · Physics 2019-07-10 S. J. Tingay , P. J Hancock

We present the results of a large scale simulation, reproducing the behavior of a data center for the build-up and maintenance of a complete catalog of space debris in the upper part of the low Earth orbits region (LEO). The purpose is to…

Dynamical Systems · Mathematics 2015-05-28 Andrea Milani , Davide Farnocchia , Linda Dimare , Alessandro Rossi , Fabrizio Bernardi

Low-earth-orbit (LEO) satellite communication systems that use millimeter-wave frequencies rely on large antenna arrays with hybrid analog-digital architectures for rapid beam steering. LEO satellites are only visible from the ground for…

Signal Processing · Electrical Eng. & Systems 2025-11-03 Anders Malthe Westerkam , Amélia Struyf , Dimitri Lederer , Troels Pedersen , François Quitin

We provide the first in situ measurements of antenna element (tile) beam shapes of the Murchison Widefield Array (MWA), a low radio-frequency interferometer and an SKA precursor. Most current MWA processing pipelines use an assumed beam…

This paper investigates joint device identification, channel estimation, and signal detection for LEO satellite-enabled grant-free random access, where a multiple-input multipleoutput (MIMO) system with orthogonal time-frequency space…

Information Theory · Computer Science 2023-08-08 Boxiao Shen , Yongpeng Wu , Wenjun Zhang , Symeon Chatzinotas , Björn Ottersten