Results 151 to 160 of about 123,093 (174)
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Radio Astronomy and Radio Telescopes
2010An astronomical object somewhere in the Planetary System, the Galaxy, a Cluster of Galaxies, or far out in the Universe may generate radio waves by one or the other physical process (a topic of Astrophysics). If the radio emission is generated inside the object, some of the radio waves propagate through the object until they may leave the radio source ...
Michael Bremer, Albert Greve
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Radio telescope for millimeter wavelengths.
Journal of Spacecraft and Rockets, 1964A 16-ft-diam radio telescope has been built to operate at frequencies up to 140 Gc (2.15-mm wavelength). The expected gain at 140 Gc is 72.5 db. Measured gain at 70 Gc is greater than 67.8 db with a beamwidth of 3.7 min of arc. The parabolic reflector comprises Invar honeycomb panels supported by a welded Invar truss; its surface is precision-swept ...
R. C. Fisher, H. S. Hoard, F. A. Onians
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Prism beamswitch for radio telescopes
Review of Scientific Instruments, 1978A dielectric prism and switching mechanism have been constructed for beamswitching a Cassegrain radio telescope. Spatially extended radio sources may be mapped without significant confusion utilizing the sensitivity and stability inherent in the conventional Dicke radiometer.
J. M. Payne, B. L. Ulich
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2007
The Square Kilometer Array (SKA) may yet become the world’s largest radio telescope, consisting of thousands of antennas (both dishes and dipoles) spread over isolated, semi-desert regions of South Africa and Australia.
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The Square Kilometer Array (SKA) may yet become the world’s largest radio telescope, consisting of thousands of antennas (both dishes and dipoles) spread over isolated, semi-desert regions of South Africa and Australia.
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Science News, 1969
In the last 30 years radio telescopes have given astronomers an entirely new picture of the universe. Radio astronomy has a distinguished record of discovering things not only unknown, but unsuspected. The record stretches from the original discovery in the 1930's that astronomical objects gave off radio waves (SNL: 6/3/33, p.
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In the last 30 years radio telescopes have given astronomers an entirely new picture of the universe. Radio astronomy has a distinguished record of discovering things not only unknown, but unsuspected. The record stretches from the original discovery in the 1930's that astronomical objects gave off radio waves (SNL: 6/3/33, p.
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Radio-Telescope Antenna Parameters
IEEE Transactions on Military Electronics, 1964Principal antenna parameters which are useful in characterizing the electrical performance of radio-telescope antennas are defined and the relations between them are established. The application of these parameters to radio astronomical measurements is discussed.
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Spectrometers for Radio Telescopes
1999When we decide to build a new radio telescope for observing at millimeter wavelengths of the electromagnetic spectrum, we have to make many very important decisions. One of these is the type of spectrometer to use. Here we will present a short description of the several choices available, with special focus on acousto-optical spectrometers.
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2003
Single antenna small radio telescopes, 30-m diameter and smaller, are often overshadowed by the few large dishes and multiple antennae arrays. Contemporary emphasis in radio astronomy is the construction of large antennae and multiple antennae arrays. Of course, the obvious reasons include greater flux sensitivity and improvement of spatial resolution.
J. Donald Cline +3 more
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Single antenna small radio telescopes, 30-m diameter and smaller, are often overshadowed by the few large dishes and multiple antennae arrays. Contemporary emphasis in radio astronomy is the construction of large antennae and multiple antennae arrays. Of course, the obvious reasons include greater flux sensitivity and improvement of spatial resolution.
J. Donald Cline +3 more
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Journal of the Institution of Electrical Engineers, 1961
Conventional methods can no longer satisfy many observational requirements in radio astronomy. New principles are being applied in a range of instruments designed for specific purposes; some of these are discussed and contrasted in this article, which is based on a lecture given at an Ordinary Meeting at Savoy Place on the 27th October 1960.
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Conventional methods can no longer satisfy many observational requirements in radio astronomy. New principles are being applied in a range of instruments designed for specific purposes; some of these are discussed and contrasted in this article, which is based on a lecture given at an Ordinary Meeting at Savoy Place on the 27th October 1960.
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Incoherent clocking for radio telescopes
Ground-based and Airborne Telescopes VIII, 2020The method of “incoherent clocking” is discussed, wherein all-digital methods using FPGAs and COTS digital fiberoptic modules and commercial (e.g. aerial) fiber routing, along with free-running local oscillators at each antenna, are used to provide a clock and timing solution for “at antenna” digitization for any cost, scale, and frequency of radio ...
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