Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
The Afcrl 29 Ft Millimeter Wave Antenna
Download The Afcrl 29 Ft Millimeter Wave Antenna full books in PDF, epub, and Kindle. Read online The Afcrl 29 Ft Millimeter Wave Antenna ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis The AFCRL 29-ft Millimeter-wave Antenna by : L. M. Keane
Download or read book The AFCRL 29-ft Millimeter-wave Antenna written by L. M. Keane and published by . This book was released on 1965 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt: A general description of AFCRL's new 29-ft parabolic antenna is given. This antenna, designed for operation at 35 Gc, has Cassegrain feed optics and a precise reflecting surfdce supported on an elevation over azimuth mount. Design parameters include a gain of 67.5 dB at 35 Gc and a pointing capability of better than =1 arc min under 30-knot wind loads, normal solar loading, and peak accelerations of .012 deg/sq sec. The servo system was designed primarily to track objects traveling at sidereal rates. A limited satellite tracking capability should exist, however. Emphasis is given to engineering aspects of the tower, mount, drive system, and reflector assembly which should provide efficient rf operation and extreme precision in pointing. (Author).
Book Synopsis The AFCRL 29-ft Millimeter-wave Antenna by : Leo M. Keane
Download or read book The AFCRL 29-ft Millimeter-wave Antenna written by Leo M. Keane and published by . This book was released on 1965 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A general description of AFCRL's new 29-ft parabolic antenna is given. This antenna, designed for operation at 35 Gc, has Cassegrain feed optics and a precise reflecting surfdce supported on an elevation over azimuth mount. Design parameters include a gain of 67.5 dB at 35 Gc and a pointing capability of better than =1 arc min under 30-knot wind loads, normal solar loading, and peak accelerations of .012 deg/sq sec. The servo system was designed primarily to track objects traveling at sidereal rates. A limited satellite tracking capability should exist, however. Emphasis is given to engineering aspects of the tower, mount, drive system, and reflector assembly which should provide efficient rf operation and extreme precision in pointing. (Author)
Download or read book Technical Abstract Bulletin written by and published by . This book was released on with total page 776 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Scientific and Technical Aerospace Reports by :
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1973 with total page 222 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Report on Research at AFCRL by : Air Force Cambridge Research Laboratories (U.S.)
Download or read book Report on Research at AFCRL written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1970 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Pointing Calibration of a High-resolution Millimeter-wave Antenna by Star Observations by : Melvin Burak
Download or read book Pointing Calibration of a High-resolution Millimeter-wave Antenna by Star Observations written by Melvin Burak and published by . This book was released on 1971 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extensive pointing calibration program for the drive system and mount of the AFCRL 29-ft millimeter-wave antenna is described. The optical pointing accuracy was determined by measuring the positioning errors of the optical axis of the antenna. Since all sources of optical pointing errors produce equivalent RF errors, all RF errors except those produced by feed system and reflector asymmetry are determined. A brief description of the antenna together with the integrated IBM 1800 data aquisition and control system, tracking software, and an accurate time-synchronization method are presented. The star tracking program, which includes a method of star selection, precession correction, and refraction correction, is described. The analysis and derivation of the various pointing error parameters used to determine the best-fitting functions that characterize the positional errors are presented. Next, the star data are reduced by fitting the nightly error measurements to the best-fitting error function from which the values of the error parameters that take into account the servo, collimation, azimuth plane tilt, elevation axis skewness, and residual refraction are determined. Finally, the results of the star data analysis and statistical data are presented. The rms residual optical pointingg error, after pointin calibration, averaged about 3 percent of the antenna beamwidth, that is, 7.5 arc seconds in both azimuth and elevation. (Author).
Book Synopsis Radiometric Observations of the Planets Jupiter, Venus, and Mars at a Wavelength of 8.6 Millimeters by : P. M. Kalaghan
Download or read book Radiometric Observations of the Planets Jupiter, Venus, and Mars at a Wavelength of 8.6 Millimeters written by P. M. Kalaghan and published by . This book was released on 1967 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Observations of the 8.6 mm radio emission from the planets Jupiter, Venus, and Mars are reported. Average disc temperatures of 140 (+18, -14)K for Jupiter, 423 (+55, -34)K for Venus over the 51 degrees to 62 degrees phase angle range, and 235 (+45, -33)K for Mars were obtained. (Author).
Book Synopsis Literature 1972, Part 1 by : Siegfried Böhme
Download or read book Literature 1972, Part 1 written by Siegfried Böhme and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 533 pages. Available in PDF, EPUB and Kindle. Book excerpt: Astronomy and Astrophysics Abstracts, which has appeared in semi-annual volumes since 1969, is de voted to the recording, summarizing and indexing of astronomical publications throughout the world. It is prepared under the auspices of the International Astronomical Union (according to a resolution adopted at the 14th General Assembly in 1970). Astronomy and Astrophysics Abstracts aims to present a comprehensive documentation of Iiterature in all fields of astronomy and astrophysics. Every effort will be made to ensure that the average time interval between the date of receipt of the original Iiterature and publication of the abstracts will not exceed eight months. This time interval is near to that achieved by monthly abstracting journals, com pared to which our system of accumulating abstracts for about six months offers the advantage of greater convenience for the user. Valurne 7 contains Iiterature published in 1972 and received before August 15, 1972; some older Iiter ature which was received late and which is not recorded in earlier volumes is also included.
Book Synopsis Government-wide Index to Federal Research & Development Reports by :
Download or read book Government-wide Index to Federal Research & Development Reports written by and published by . This book was released on 1966-02 with total page 1050 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Report on Research at AFCRL. by : Air Force Cambridge Research Laboratories (U.S.)
Download or read book Report on Research at AFCRL. written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1962-07 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmental Research Papers written by and published by . This book was released on 1967 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis OAR Cumulative Index of Research Results by :
Download or read book OAR Cumulative Index of Research Results written by and published by . This book was released on with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis OAR Quarterly Index of Current Research Results by : United States. Air Force. Office of Aerospace Research
Download or read book OAR Quarterly Index of Current Research Results written by United States. Air Force. Office of Aerospace Research and published by . This book was released on 1965 with total page 576 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Earth-to-space Communications at Millimeter Wavelengths by : Edward E. Altshuler
Download or read book Earth-to-space Communications at Millimeter Wavelengths written by Edward E. Altshuler and published by . This book was released on 1965 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is expected that with the exploration of outer space, a requirement for high data rate earth-to-space communication channels will arise. A program to investigate the feasibility of using the millimeter-wave region of the spectrum for this application is presented. The theory of atmospheric attenuation resulting from losses due to absorption, scattering and refraction processes is reviewed and used to estimate propagation losses produced by atmospheric gases, clouds and precipitation. Curves of total atmospheric attenuation and noise level as a function of meteorological parameters and antenna elevation angle are also presented. A series of experiments designed to obtain as much information as possible on the limitations imposed by the atmosphere on millimeter-wave propagation is considered. Although experiments using natural celestial bodies such as the sun, moon, planets and galaxies as radio sources are emphasized, those which would utilize aircraft, rockets and satellites are also mentioned. Finally, the characteristics of a recently installed precision 29-ft antenna designed to operate at 35 Gc (wavelength = 8.6 mm) with a traveling-wave maser as a preamplifier for the radiometer are outlined along with the specific experiments for which this antenna system will be used. (Author).
Book Synopsis Pointing Error Correction for Millimeter Wave Spectroheliograms by : Michael J. Neary
Download or read book Pointing Error Correction for Millimeter Wave Spectroheliograms written by Michael J. Neary and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The AFCRL 29-ft millimeter wave antenna at the Prospect Hill Millimeter Wave Observatory, Waltham, Massachusetts, is used to make solar maps (spectroheliograms), at a wavelength of 8.6 mm, for solar forecasting purposes. The half-power beamwidth of the antenna, although only 4 min of arc, is not narrow enough to detect the smaller hot regions that can develop into active centers on the sun. To overcome this limitation, a data-reduction process that can effectively narrow the beamwidth of the antenna, so that finer details on the maps will be visible, is needed. A computer program that can effectively narrow the beamwidth of the scanning antenna system by restoring and enhancing the antenna output has been applied to the Prospect Hill maps. It is believed that the enhanced maps can be further improved if a quiet sun component, or mean map, is subtracted from daily maps before the restoration is attempted. This report describes the technique used on the Prospect Hill IBM 1800 computer system to center the mean and daily maps on a common heliographic reference to effect the subtraction. (Author).
Book Synopsis OAR Cumulative Index of Research Results by : United States. Air Force. Office of Aerospace Research
Download or read book OAR Cumulative Index of Research Results written by United States. Air Force. Office of Aerospace Research and published by . This book was released on 1965 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Solar Observations at 8.6-mm Wavelength by : Paul M. Kalaghan
Download or read book Solar Observations at 8.6-mm Wavelength written by Paul M. Kalaghan and published by . This book was released on 1970 with total page 58 pages. Available in PDF, EPUB and Kindle. Book excerpt: The advent of manned space flights has focused attention on the biological threat posed by solar proton flares. In an effort to close one of the gaps in the observation of the solar spectrum, AFCRL has initiated a high resolution millimeter wavelength solar observation program. This report covers the observational approach and initial findings of this program based upon observations from May to December 1968. The equipment and procedures used to produce spectroheliograms at 8.6 mm, using the AFCRL 29-ft Millimeter Wave Antenna, are described. The quiet sun at 8.6 mm appeared to have a brightness temperature of 8400 plus or minus 600 K blackbody and a 'radio diameter' 3 percent greater than the optical disk. The presence of active regions during this period was characterized by localized enhanced regions exhibiting temperature increases from 1 to 28 percent of the quiet sun level. The enhancement and the positions of these regions have been compared with 9.1-cm radio data and various other optical data. The locations of the 8.6-mm enhanced regions are contained within calcium plages. All proton events observed originated only in highly enhanced (Class III) regions. Further observations are in progress to increase the sample size of observed proton events to further refine the possibility of prediction of these events. (Author).
