English
Related papers

Related papers: Phased array observations with infield phasing

200 papers

We undertake the first targeted search at 1.5 GHz for radio emission from the variable $\gamma$-ray pulsar PSR J2021$+$4026. This radio-quiet pulsar assumes one of two stable $\gamma$-ray emission states, between which it transitions on a…

High Energy Astrophysical Phenomena · Physics 2023-05-24 B. Shaw , B. W. Stappers , P. Weltevrede , C. A. Jordan , M. B. Mickaliger , A. G. Lyne

Meta distribution is a fine-grained unified performance metric that enables us to evaluate the {reliability and latency} of next generation wireless networks, in addition to the conventional coverage probability. In this paper, using…

Signal Processing · Electrical Eng. & Systems 2019-12-10 Hazem Ibrahim , Hina Tabassum , Uyen T. Nguyen

We present a study of shape, spectra and polarization properties of giant pulses (GPs) from the Crab pulsar at the very high frequencies of 8.5 and 15.1 GHz. Studies at 15.1 GHz were performed for the first time. Observations were conducted…

We present low-frequency observations with the Giant Metrewave Radio Telescope (GMRT) of a sample of giant radio sources (GRSs), and high-frequency observations of three of these sources with the Very Large Array (VLA). From multifrequency…

Astrophysics · Physics 2009-11-13 C. Konar , M. Jamrozy , D. J. Saikia , J. Machalski

We emphasize the importance of observations of young supernovae in wide radio band. We argue on the basis of observational results that only high or only low frequency data is not sufficient to get full physical picture of the shocked…

Astrophysics · Physics 2007-05-23 Poonam Chandra , Alak Ray

Integrated pulse profiles at 8.6~GHz obtained with the Shanghai Tian Ma Radio Telescope (TMRT) are presented for a sample of 26 pulsars. Mean flux densities and pulse width parameters of these pulsars are estimated. For eleven pulsars these…

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

Most neutron stars are expected to be born in supernovae, but only about half of supernova remnants (SNRs) are associated with a compact object. In many cases, a supernova progenitor may have resulted in a black hole. However, there are…

High Energy Astrophysical Phenomena · Physics 2021-04-02 S. Sett , R. P. Breton , C. J. Clark , M. H. Kerkwijk , D. L. Kaplan

We present a summary of gamma-ray millisecond pulsar (MSP) observations with the Fermi Large Area Telescope. The radio and gamma-ray light curves of these MSPs have been modeled in the framework of the retarded vacuum dipole magnetic field.…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Tyrel J. Johnson , Christo Venter , Alice K. Harding , Lucas Guillemot

In this paper, the integrated continuum radio spectrum of supernova remnant (SNR) W44 was analyzed up to 70 GHz, testing the different emission models that can be responsible for its particular shape. The observations by the Planck space…

High Energy Astrophysical Phenomena · Physics 2015-12-02 D. Onić

We consider sparse array beamfomer design achieving maximum signal-to interference plus noise ratio (MaxSINR). Both array configuration and weights are attuned to the changing sensing environment. This is accomplished by simultaneously…

Signal Processing · Electrical Eng. & Systems 2019-10-24 Syed A. Hamza , Moeness G. Amin

With the ever-increasing sensitivity and timing baselines of modern radio telescopes, a growing number of pulsars are being shown to exhibit transitions in their rotational and radio emission properties. In many of these cases, the two are…

High Energy Astrophysical Phenomena · Physics 2022-05-11 B. Shaw , B. W. Stappers , P. Weltevrede , P. R. Brook , A. Karastergiou , C. A. Jordan , M. J. Keith , M. Kramer , A. G. Lyne

Our work aims to investigate the polarisation convention of the Giant Metrewave Radio Telescope (GMRT) radio telescope and understand whether the telescope follows the standard IAU/IEEE convention. The GMRT antennas are prime focus…

Instrumentation and Methods for Astrophysics · Physics 2023-10-10 Poonam Chandra , S. Suresh Kumar , Sanjay Kudale , Devojyoti Kansabanik , Barnali Das , Preeti Kharb , Silpa Sasikumar , Biny Sebastian

A "pulsar timing array" (PTA), in which observations of a large sample of pulsars spread across the celestial sphere are combined, allows investigation of "global" phenomena such as a background of gravitational waves or instabilities in…

High-precision timing of millisecond pulsars (MSPs) over years to decades is a promising technique for direct detection of gravitational waves at nanohertz frequencies. Time-variable, multi-path scattering in the interstellar medium is a…

High Energy Astrophysical Phenomena · Physics 2015-06-22 Anne M. Archibald , Vladislav I. Kondratiev , Jason W. T. Hessels , Daniel R. Stinebring

Pulsar detection and timing experiments are applications where adaptive filters seem eminently suitable tools for radio-frequency-interference (RFI) mitigation. We describe a novel variant which works well in field trials of pulsar…

Astrophysics · Physics 2015-06-24 M. Kesteven , G. Hobbs , R. Clement , B. Dawson , R. Manchester , T. Uppal

The use of large arrays might be the solution to the capacity problems in wireless communications. The signal-to-noise ratio (SNR) grows linearly with the number of array elements $N$ when using Massive MIMO receivers and half-duplex…

Information Theory · Computer Science 2023-02-22 Emil Björnson , Luca Sanguinetti

Radio pulsar timing array (PTA) experiments using millisecond pulsars (MSPs) are beginning to detect nHz gravitational waves (GWs). MSPs are bright GeV gamma-ray emitters, and all-sky monitoring of about 100 MSPs with the Fermi Large Area…

High Energy Astrophysical Phenomena · Physics 2025-12-18 Matthew Kerr , Zorawar Wadiasingh , Adrien Laviron , Constantinos Kalapotharakos , Thankful Cromartie , Tyler Cohen

We report on the discovery of gamma-ray pulsations from five millisecond pulsars (MSPs) using the Fermi Large Area Telescope (LAT) and timing ephemerides provided by various radio observatories. We also present confirmation of the gamma-ray…

This paper investigates the effect of oscillator phase noise on a multiuser millimeter wave (mmWave) massive MIMO uplink as we scale up the number of base station antennas, fixing the load factor, defined as the ratio of the number of…

Signal Processing · Electrical Eng. & Systems 2019-10-22 Maryam Eslami Rasekh , Mohammed Abdelghany , Upamanyu Madhow , Mark Rodwell