By Topic

Proceedings of the IEEE

Issue 9 • Date Sept. 1973

Filter Results

Displaying Results 1 - 25 of 50
  • [Front cover and table of contents]

    Publication Year: 1973, Page(s): c1
    Request permission for commercial reuse | PDF file iconPDF (546 KB)
    Freely Available from IEEE
  • Scanning the issue

    Publication Year: 1973, Page(s):1172 - 1173
    Request permission for commercial reuse | PDF file iconPDF (194 KB)
    Freely Available from IEEE
  • Extragalactic radio sources

    Publication Year: 1973, Page(s):1174 - 1182
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1043 KB)

    More than 10 000 individual discrete sources have been detected by radio surveys made at frequencies from 10 MHz to 5 GHz. Although only a few hundred of these are reliably identified with galaxies or quasars, it is widely believed that the overwhelming majority are extragalactic. As a result of the rapid improvement in the sensitivity and the resolution of radio telescopes, the coordinates of man... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Neutral hydrogen and galactic structure

    Publication Year: 1973, Page(s):1182 - 1192
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1187 KB)

    Observations of the 21-cm line of neutral hydrogen give the best method for mapping the spiral structure of our galaxy, but there are still difficulties of interpretation. These arise from the need to infer the distance of any hydrogen concentration from its radial velocity, under circumstances where the velocity field and the structural pattern must both be derived from the same observations. The... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Introduction to very-long-baseline interferometry

    Publication Year: 1973, Page(s):1192 - 1197
    Cited by:  Papers (10)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (671 KB)

    Long-baseline interferometry achieves high resolution by using two or more widely separated radio telescopes and recording video signals on magnetic tapes, which are later brought together and cross-correlated. This paper contains discussions of the coherence and timing requirements and of calibration procedures. Applications to measuring brightness distributions and to spectroscopy are reviewed b... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Molecular clouds in the galaxy

    Publication Year: 1973, Page(s):1198 - 1204
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (855 KB)

    Spectral-line radio astronomy has revealed over 50 molecular lines in the past four years. These lines correspond to 24 interstellar molecules, mostly organic, which are contained in dust clouds. Molecular clouds play an essential part in the evolutionary cycle taking place in our galaxy. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The properties of pulsars

    Publication Year: 1973, Page(s):1205 - 1211
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (752 KB)

    The principal observed properties of pulsars and their theoretical interpretation are reviewed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Earth-rotation aperture synthesis

    Publication Year: 1973, Page(s):1211 - 1218
    Cited by:  Papers (22)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1063 KB)

    Resolution for radio astronomy in the order of 1" is necessary for the study of distant radio galaxies and quasars, for detecting faint sources, and for the mapping of clouds of hydrogen and other molecules. To obtain these resolutions many new or planned radio instruments use arrays of moderate size radio telescopes to synthesize large physical apertures. These instruments are generally composed ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Mapping of planetary surfaces by radar

    Publication Year: 1973, Page(s):1219 - 1225
    Cited by:  Papers (19)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (788 KB)

    A review is presented of the several methods which are available for the mapping of both reflectivity and topography of planetary surfaces by ground-based radar. Emphasis is placed on observational methods rather than interpretation of results. The various observational schemes are illustrated by recent observational results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Very-long-baseline interferometry techniques applied to problems of geodesy, geophysics, planetary science, astronomy, and general relativity

    Publication Year: 1973, Page(s):1225 - 1230
    Cited by:  Papers (2)  |  Patents (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (731 KB)

    Very-long-baseline interferometry (VLBI) techniques have already been used to determine the vector separations between antennas thousands of kilometers apart to within 2 m and the directions of extragalactic radio sources to 0.1", and to track an artificial satellite of the earth and the Apollo Lunar Rover on the surface of the moon. The relative locations of the Apollo Lunar Surface Experiment Pa... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Long wavelength VLBI

    Publication Year: 1973, Page(s):1230 - 1233
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (418 KB)

    The application of very-long baseline interferometry (VLBI) techniques at meter and decameter wavelengths has proven to be a unique tool for studying a number of different phenomena. Because of the high angular resolution which we achieve with VLBI, candidate objects for study include the compact nuclei and "jets" associated with quasars and radio galaxies, pulsars, small knots in galactic superno... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Tracking the Apollo Lunar Rover with interferometry techniques

    Publication Year: 1973, Page(s):1233 - 1236
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (395 KB)

    Apollo 16 and 17 Lunar Rover position history while transporting astronauts over the lunar surface has been determined to a resolution of better than 1 m and uncertainties of less than 25 m utilizing a specialized very-long baseline interferometry (VLBI) tracking technique. This paper describes the technique, discusses the National Aeronautics and Space Administration worldwide tracking system use... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Spectral-line analysis of very-long-baseline interferometric data

    Publication Year: 1973, Page(s):1236 - 1242
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (647 KB)

    Several topics concerning the processing and interpretation of data obtained with very-long-baseline (VLB) interferometers--i.e., tape-recorder interferometers--from spectral-line radio sources are discussed. The instrumental phase shifts are traced through the interferometer. The spectral resolution and normalization of the visiblity spectrum are discussed. Expressions for estimating fringe ampli... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The NRAO tape-recorder interferometer system

    Publication Year: 1973, Page(s):1242 - 1248
    Cited by:  Papers (33)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (827 KB)

    Several tape-recorder interferometer systems have been constructed in the last few years. These systems are used for connecting existing radio-telescope systems into interferometers, with baselines ranging from a few kilometers to nearly the diameter of the earth. The NRAO Mark II interferometer system is in wide use. This, and the fact that its properties are typical of those of such systems in g... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Stanford five-element radio telescope

    Publication Year: 1973, Page(s):1249 - 1257
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (952 KB)

    The Stanford radio telescope array is a fast image-forming interferometer using earth rotation synthesis to produce a brightness map of the continuum radiation from a portion of the sky using data obtained in one 10-h observation. The array consists of five 18.3-m diam paraboloid antennas mounted on an east-west line in such a way that pairs of antennas span all spacings from 1 to 9 times the unit... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The synthesis radio telescope at Westerbork

    Publication Year: 1973, Page(s):1258 - 1266
    Cited by:  Papers (7)  |  Patents (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1227 KB)

    The synthesis radio telescope (SRT) is an array of 20 simultaneous interferometers formed by 10 fixed and 2 movable antennas on an E-W baseline of 1600 m, operating on the principle of rotational aperture synthesis. It is capable of observing continuum radiation in 4 Stokes parameters and line radiation at 50-, 21-, and 6-cm wavelengths. This paper centers on a description of the electronic system... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A new southern hemisphere synthesis radio telescope

    Publication Year: 1973, Page(s):1266 - 1270
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (595 KB)

    An earth-rotational synthesis radio telescope is now operating at a wavelength of 21 cm at Fleurs, near Sydney, Australia. The telescope produces a map of a 1.5 square-degree region of sky in an observing time of 12 to 16 h. In the first stage the resolution is 40" and the sensitivity (5 times rms noise fluctuations) is about 70 × 10-29. A full range of scanning angles is available... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A supersynthesis radio telescope for neutral hydrogen spectroscopy at the dominion radio astrophysical observatory

    Publication Year: 1973, Page(s):1270 - 1276
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (657 KB)

    A radio telescope designed for studies of the 21-cm line of neutral hydrogen is described. It combines the techniques of aperture synthesis and digital correlation spectrometry to achieve an angular resolution of 1 arc min within an area of sky of 2° diameter and a frequency resolution variable from 3 to 100 kHz with 80 channels. The telescope comprises four 9-m paraboloids, two fixed and two... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Clark lake array

    Publication Year: 1973, Page(s):1276 - 1277
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (235 KB)

    A powerful new instrument for meter and dekameter wavelength radio astronomy is described. It will soon be available for both solar and sidereal studies. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The Hat Creek millimeter-wave interferometer

    Publication Year: 1973, Page(s):1278 - 1282
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (571 KB)

    A fixed-baseline millimeter-wave interferometer, operating initially at 13.5 mm, has been put into operation at the Hat Creek Observatory as the first step in the development of a two-element aperture synthesis telescope. The first system consists of a 3-m antenna and a 6-m antenna spaced 265 m apart. Large receiver bandwidths may be used at high frequencies, and this system employs an intermediat... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An 8-mm interferometer for solar radio astronomy at Bordeaux, France

    Publication Year: 1973, Page(s):1282 - 1284
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (359 KB)

    A small two-antenna interferometer working at a wavelength of 8 mm, with a baseline of 64 m is now completed at the Observatory in Bordeaux. The new instrument is designed for solar studies and for experimentation in millimeter-wave interferometry. The main characteristics are given with some details on techniques used, in particular for local-oscillator (LO) transmission and phase stability, and ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An aperture-synthesis interferometer at Ooty for operation at 327 MHz

    Publication Year: 1973, Page(s):1285 - 1287
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (424 KB)

    A 3.5-km long interferometer consisting of the 530 by 30 m Ooty radio telescope, two 13.5-m diameter dishes, and a 5-m diameter dish are described. For generating coherent local-oscillator signals for the interferometer, a simple phase-stable radio link has been developed which uses the sum-frequency method proposed for the VLA antenna. The interferometer, expected to be in operation in 1973, will... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The 100-meter radio telescope at Effelsberg

    Publication Year: 1973, Page(s):1288 - 1295
    Cited by:  Papers (15)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (1024 KB)

    The 100-m fully steerable radio telescope of the Max-Planck-Institut für Radioastronomie (MPIfR) has now been in service for over a year. The telescope was designed to allow observations in the decimeter and centimeter wavelength regions, with the vastly improved resolution given by the 100-m diameter. During construction of the telescope measurements were made at a wavelength of 75 cm. Since... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pulsar receivers and data processing

    Publication Year: 1973, Page(s):1295 - 1298
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (440 KB)

    The rapid variabilty of pulsar signals and the dispersive nature of the interstellar medium introduce a number of problems which are not inherent in other radio-astronomical observations. These problems are discussed and some of the techniques currently being used to cope with them are described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Pulsars as probes of the interstellar medium

    Publication Year: 1973, Page(s):1298 - 1302
    Request permission for commercial reuse | Click to expandAbstract | PDF file iconPDF (539 KB)

    Pulsar observations offer an opportunity to determine the distributions of the magnetic field, electron density, and neutral atomic hydrogen density in the interstellar space. Pulse polarization and time of arrival measurements indicate a relatively uniform magnetic field of about 3 µG, whereas new distance measurements through 21-cm line absorption indicate an electron density of about 0.03 ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The most highly-cited general interest journal in electrical engineering and computer science, the Proceedings is the best way to stay informed on an exemplary range of topics.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
H. Joel Trussell
North Carolina State University