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Related papers: Phased array observations with infield phasing

200 papers

Phase noise caused by an inhomogeneous, time-variable water vapor distribution in our atmosphere reduces the angular resolution, visibility amplitude and coherence time of millimeter and submillimeter wavelength interferometers. We present…

Astrophysics · Physics 2009-11-10 James B. Battat , Raymond Blundell , James M. Moran , Scott Paine

We derive scaling laws for the signal-to-noise ratio of the optimal cross-correlation statistic, and show that the large power-law increase of the signal-to-noise ratio as a function of the the observation time $T$ that is usually assumed…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Xavier Siemens , Justin Ellis , Fredrick Jenet , Joseph D. Romano

We present a practical implementation of a phase-coherent mapping technique for pulsar timing arrays that resolves the full complex polarisation state of the gravitational-wave sky as a function of direction and frequency. Unlike standard…

High Energy Astrophysical Phenomena · Physics 2026-04-22 Małgorzata Curyło , Eric Thrane , Paul D. Lasky , Dawson S. Gaynor

Giant pulses emitted by PSR B1937+21 are bright, intrinsically impulsive bursts. Thus, the observed signal from a giant pulse is a noisy but direct measurement of the impulse response from the ionized interstellar medium. We use this fact…

High Energy Astrophysical Phenomena · Physics 2023-10-12 Nikhil Mahajan , Marten H. van Kerkwijk

One of the primary objectives for Pulsar Timing Arrays (PTAs) is to detect a stochastic background generated by the incoherent superposition of gravitational waves (GWs), in particular from the cosmic population of supermassive black hole…

High Energy Astrophysical Phenomena · Physics 2014-09-30 Chiara M. F. Mingarelli , Trevor Sidery

The discovery and timing follow-up of millisecond pulsars (MSPs) are necessary not just for their usefulness in Pulsar Timing Arrays (PTAs) but also for investigating their own intriguing properties. In this work, we provide the findings of…

High Energy Astrophysical Phenomena · Physics 2023-11-01 Shyam S. Sharma , Jayanta Roy , Bhaswati Bhattacharyya , Lina Levin

The concept of SNR enhancement in impulse radio transceivers based on phasers of opposite chirping slopes is introduced. It is shown that signal to-noise radio (SNR) enhancements by factors M2 and M are achieved for burst noise and Gaussian…

Optics · Physics 2014-02-20 Babak Nikfal , Qingfeng Zhang , Christophe Caloz

The results of four recently introduced beamforming schemes for phased array systems are discussed, each of which is capable to provide high sensitivity and accurate polarimetric performance of array-based radio telescopes. Ideally, a radio…

Instrumentation and Methods for Astrophysics · Physics 2011-08-30 Marianna V. Ivashina , Stefan J. Wijnholds , Rob Maaskant , Karl F. Warnick

Radio pulses from pulsars are affected by plasma dispersion, which results in a frequency-dependent propagation delay. Variations in the magnitude of this effect lead to an additional source of red noise in pulsar timing experiments,…

This paper addresses the standard generalized likelihood ratio test (GLRT) detection problem of weak signals in background noise. In so doing, we consider a nonfluctuating target embedded in complex white Gaussian noise (CWGN), in which the…

Signal Processing · Electrical Eng. & Systems 2021-07-12 Fernando Darío Almeida García , Marco Antonio Miguel Miranda , José Cândido Silveira Santos Filho

We present 610 MHz spectropolarimetric images from the Giant Metrewave Radio Telescope (GMRT). We discuss the properties of the GMRT's full-polarisation mode in detail and provide a technical characterisation of the instrument's…

Instrumentation and Methods for Astrophysics · Physics 2013-12-02 J. S. Farnes , D. A. Green , N. G. Kantharia

Fringe tracking in interferometers is typically analyzed with the implicit assumption that there is a single phase associated with each telescope in the array. If the telescopes have apertures significantly larger than r0 and only partial…

Astrophysics · Physics 2009-11-13 David F. Buscher , John S. Young , Fabien Baron , Christopher A. Haniff

We present the first spectropolarimetric radio observations that apply Rotation Measure (RM) Synthesis to interferometric data from the Giant Metrewave Radio Telescope (GMRT) at 610 MHz. Spectropolarimetry requires measurement of a large…

Instrumentation and Methods for Astrophysics · Physics 2013-09-19 J. S. Farnes , D. A. Green , N. G. Kantharia

Pulsar radio emission undergoes dispersion due to the presence of free electrons in the interstellar medium (ISM). The dispersive delay in the arrival time of pulsar signal changes over time due to the varying ISM electron column density…

The millimeter wave (mmWave) frequencies are likely to play a significant role in fifth-generation (5G) cellular systems. A key challenge in developing systems in these bands is the potential for rapid channel dynamics: since mmWave signals…

Networking and Internet Architecture · Computer Science 2016-04-20 Marco Giordani , Marco Mezzavilla , Aditya Dhananjay , Sundeep Rangan , Michele Zorzi

The supernova remnant (SNR) G315.4$-$2.3 (MSH 14$-$63 or RCW 86) exhibits strong emission across the electromagnetic spectrum. Radio polarization observations probe magnetic fields and will help to understand the evolution of the SNR. We…

Astrophysics of Galaxies · Physics 2026-04-22 X. Chen , X. Sun , J. F. Kaczmarek , B. M. Gaensler , P. Slane , J. L. West

Pulsar timing arrays (PTAs) are essential tools for detecting the stochastic gravitational wave background (SGWB), but their analysis faces significant computational challenges. Traditional methods like Markov-chain Monte Carlo (MCMC)…

Instrumentation and Methods for Astrophysics · Physics 2024-12-30 Bo Liang , Chang Liu , Tianyu Zhao , Minghui Du , Manjia Liang , Ruijun Shi , Hong Guo , Yuxiang Xu , Li-e Qiang , Peng Xu , Wei-Liang Qian , Ziren Luo

Context. We have investigated the multiwavelength emission of PSR J2021+4026, the only isolated gamma-ray pulsar known to be variable, which in October 2011 underwent a simultaneous change in gamma-ray flux and spin-down rate, followed by a…

High Energy Astrophysical Phenomena · Physics 2023-08-16 M. Razzano , A. Fiori , P. M. Saz Parkinson , R. P. Mignani , A. De Luca , A. K. Harding , M. Kerr , M. Marelli , V. Testa

A lunar orbit interferometer array suffers from a number of systematics. Beyond systematics induced by the imaging algorithm itself and thermal noise considered in Paper I, phase errors due to instrumental inconsistency between receivers,…

Instrumentation and Methods for Astrophysics · Physics 2026-04-01 Meng Zhou , Furen Deng , Yidong Xu , Li Zhou , Xuelei Chen

Phased array feeds (PAFs) for reflector antennas offer the potential for increased reflector field of view and faster survey speeds. To address some of the development challenges that remain for scientifically useful PAFs, including…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Jonathan Landon , Michael Elmer , Jacob Waldron , David Jones , Alan Stemmons , Brian D. Jeffs , Karl F. Warnick , J. Richard Fisher , Roger D. Norrod