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Radio astronomy observations in the coming decade will require new levels of sensitivity while mapping large regions of space with much greater efficiency than is achieved with current telescopes. This requires new instrumentation with the…

天体物理仪器与方法 · 物理学 2009-09-30 Matthew A. Morgan , J. Richard Fisher

Since 2011 Ventspils International Radio Astronomy Centre has been involved in the large scale infrastructure project which allowed significant speeding-up of the upgrading activities related to radio telescopes RT-32 and RT-16 as to its…

天体物理仪器与方法 · 物理学 2020-08-14 Vladislavs Bezrukovs , Marcis Bleiders , Arturs Orbidans , Dmitrijs Bezrukovs

Radio communication through attenuating media necessitates the use of very-low frequency (VLF) and ultra-low frequency (ULF) carrier bands, which are frequently used in underwater and under-ground communication applications. Quantum sensing…

原子物理 · 物理学 2020-03-09 Stuart J. Ingleby , Iain C. Chalmers , Terry E. Dyer , Paul F. Griffin , Erling Riis

Context. This paper presents a detailed description of the Decametre Pulsar and Transient Survey of the Northern Sky that was carried out in 2012-2017 using the world's largest radio telescope at decametre wavelengths - UTR-2 in Ukraine.…

Summarizes current status of radio interferometry at radio frequencies between Earth-based receivers, for astrometric and geodetic applications. Emphasizes theoretical models of VLBI observables that are required to extract results at the…

天体物理学 · 物理学 2008-11-26 Ojars J. Sovers , John L. Fanselow , Christopher S. Jacobs

This review arose from the European Radio Astronomy Technical Forum (ERATec) meeting held in Firenze, October 2015, and aims to highlight the breadth and depth of the high-impact science that will be aided and assisted by the use of…

This paper outlines some new observational and data processing techniques for enhancing the dynamic range of low frequency images obtained with the Giant Metrewave Radio Telescope. We illustrate new software tools developed to facilitate…

天体物理仪器与方法 · 物理学 2011-02-02 Peeyush Prasad , C. R. Subrahmanya

Digital radio arrays are widely used for the low-frequency radio astronomy as well as for detection of air-showers induced by high-energy cosmic rays and neutrinos. Since the radio emission from air-showers forms short broadband pulses with…

Dual sideband (2SB) receivers are well suited for the spectral observation of complex astronomical signals over a wide frequency range. They are extensively used in radio astronomy, their main advantages being to avoid spectral confusion…

天体物理仪器与方法 · 物理学 2018-05-17 Ricardo Finger , Patricio Mena , Nicolas Reyes , Rafael Rodriguez , Leonardo Bronfman

The Venusian surface has been studied by measuring radar reflections and thermal radio emission over a wide spectral region of several centimeters to meter wavelengths from the Earth-based as well as orbiter platforms. The radiometric…

地球与行星天体物理 · 物理学 2017-09-28 Nithin Mohan , Subhashis Roy , Govind Swarup , Divya Oberoi , Niruj Mohan Ramanujam , Suresh Raju C , Anil Bhardwaj

We detail the use of the University of Tasmania's (UTAS) optical and radio telescopes to conduct observations of near-Earth asteroids from 2021 to 2024. The Canberra Deep Space Communication Complex transmitted a radio signal at 7159.45…

Radio reception relies on antennas for the collection of electromagnetic fields carrying information, and receiver elements for demodulation and retrieval of the transmitted information. Here we demonstrate an atom-based receiver for AM and…

原子物理 · 物理学 2021-08-12 David A. Anderson , Rachel E. Sapiro , Georg Raithel

A variety of pulsar studies, ranging from high precision astrometry to tests for theories of gravity, require high time resolution data. Few such observations at more than two frequencies below 1 GHz are available. Giant Meterwave Radio…

天体物理学 · 物理学 2007-05-23 Bhal Chandra Joshi , Sunil Ramakrishna

The development of the advanced Radio Frequency Timer of electrons is described. It is based on a helical deflector, which performs circular or elliptical sweeps of keV electrons, by means of 500 MHz radio frequency field. By converting a…

Measurements of a wide variety of aerial phenomena such as drones, birds, planes, and other aerial objects can in principle be obtained from open access radio detection and ranging equipment. Passive strategies involve existing cell towers…

科普物理 · 物理学 2022-03-17 Karl Svozil

Decameter wavelength radio emission is finely structured in solar bursts. For their research it is very important to use a sufficient sensitivity of antenna systems. In this paper we study an influence of the radiotelescope-antenna…

This paper describes a 50 MHz system being developed for GMRT to provide imaging capability in the frequency range 30-90MHz. Due to its larger collecting area and higher antenna efficiency, the low frequency GMRT system will be several…

天体物理仪器与方法 · 物理学 2009-05-12 N. Udaya Shankar , K. S. Dwarakanath , Shahram Amiri , R. Somashekar , B. S. Girish , Wences Laus , Arvind Nayak

Increasing levels of Radio Frequency Interference (RFI) are a problem for research in radio astronomy. Various techniques to suppress RFI and extract astronomical signals from data affected by interference are being tried out. However,…

天体物理学 · 物理学 2007-05-23 K. Jeeva Priya , D. Anish Roshi

We observed the pair of radio sources 1150+812 and 1803+784 in November 1993 with a VLBI array, simultaneously recording at 8.4 and 2.3 GHz. We determined the angular separation between the two sources with submilliarcsecond accuracy by…

天体物理学 · 物理学 2009-10-31 M. A. Perez-Torres , J. M. Marcaide , J. C. Guirado , E. Ros

Recently we had reported commissioning of a prototype for pulsar observations at low radio frequencies (<100 MHz) using log-periodic dipole antennas (LPDAs) in the Gauribidanur Radio Observatory near Bangalore in India. The aforementioned…

天体物理仪器与方法 · 物理学 2024-04-24 Kshitij S. Bane , Indrajit V. Barve , G. V. S. Gireesh , C. Kathiravan , R. Ramesh
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