Related papers: MWA Tied-Array Processing I: Calibration and Beamf…
Modern MIMO communication systems are almost exclusively designed under the assumption of locally plane wavefronts over antenna arrays. This is known as the far-field approximation and is soundly justified at sub-6-GHz frequencies at most…
The Submillimeter Array (SMA) is an array of 8 antennas operating at millimeter and submillimeter wavelengths on Maunakea, Hawaii, operated by the Smithsonian Astrophysical Observatory and Academia Sinica Institute of Astronomy and…
Measurements of 21 cm Epoch of Reionization (EoR) structure are subject to systematics originating from both the analysis and the observation conditions. Using 2013 data from the Murchison Widefield Array (MWA), we show the importance of…
In this paper we build upon recent work in the radio astronomy community to experimentally demonstrate the viability of passive radar for Space Situational Awareness. Furthermore, we show that the six state parameters of objects in orbit…
Interferometric arrays seeking to measure the 21 cm signal from the Epoch of Reionization must contend with overwhelmingly bright emission from foreground sources. Accurate recovery of the 21 cm signal will require precise calibration of…
The Atacama Millimeter/submillimeter Array (ALMA) Phasing Project (APP) has developed and deployed the hardware and software necessary to coherently sum the signals of individual ALMA antennas and record the aggregate sum in Very Long…
With multi-GHz bandwidth, Terahertz (THz) beamforming has drawn increasing attention in the sixth generation (6G) and beyond communications. Existing beamforming designs mainly focus on a compact antenna array where typical communication…
The CHARA Array is a six 1-m telescope optical and near infrared interferometer located at the Mount Wilson Observatory in southern California and operated by the Center for High Angular Resolution Astronomy of Georgia State University. The…
In radio astronomy, holography is a commonly used technique to create an image of the electric field distribution in the aperture of a dish antenna. The image is used to detect imperfections in the reflector surface. Similarly, holography…
Drift scan observations provide the broad sky coverage and instrumental stability needed to measure the Epoch of Reionization (EoR) 21-cm signal. In such observations, the telescope's pointing center (PC) moves continuously on the sky. The…
The low-frequency radio telescope of the Square Kilometre Array (SKA-Low), currently under construction in the remote Murchison shire in the Western Australia's outback, will observe the sky between 50 MHz and 350 MHz with unprecedented…
LWA1 is a new large radio telescope array operating in the frequency range 10-88 MHz, located in central New Mexico. The telescope consists of 260 pairs of dipole-type antennas whose outputs are individually digitized and formed into beams.…
We present observations of high-amplitude rapid (2 s) variability toward two bright, compact extragalactic radio sources out of several hundred of the brightest radio sources in one of the 30x30 deg MWA Epoch of Reionization fields using…
We present a search for prompt radio emission associated with the short-duration gamma-ray burst (GRB) 150424A using the Murchison Widefield Array (MWA) at frequencies from 80-133 MHz. Our observations span delays of 23 s-30 min after the…
Pulsar radio emission and its polarization are observed to evolve with frequency. This frequency dependence is key to the emission mechanism and the structure of the radio beam. With the new Ultra-Wideband receiver (UWL) on the Parkes radio…
Low-frequency polarisation observations of pulsars, facilitated by next-generation radio telescopes, provide powerful probes of astrophysical plasmas that span many orders of magnitude in magnetic field strength and scale: from pulsar…
Astronomical widefield imaging of interferometric radio data is computationally expensive, especially for the large data volumes created by modern non-coplanar many-element arrays. We present a new widefield interferometric imager that uses…
We present the results of a pilot study search for Fast Radio Bursts (FRBs) using the Murchison Widefield Array (MWA) at low frequencies (139 - 170 MHz). We utilised MWA data obtained in a routine imaging mode from observations where the…
Rapid beam alignment is required to support high gain millimeter wave (mmW) communication links between a base station (BS) and mobile users (MU). The standard IEEE 802.11ad protocol enables beam alignment at the BS and MU through a lengthy…
Wireless backhaul communication has been recently realized with large antennas operating in the millimeter wave (mmWave) frequency band and implementing highly directional beamforming. In this paper, we focus on the alignment problem of…