Download or read book High gain UHF Backfire Antenna for Communications Telemetry and Radio Astronomy written by Hermann W. Ehrenspeck and published by . This book was released on 1967 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The backfire antenna described combines the structural advantages of a single endfire with the high gain of a reflector antenna. With its principal application in the gain range between 15 and 30 dB where ordinary endfire antennas become impractically long and paraboloidal antennas too expensive, it should prove to be especially advantageous for telemetry and radio astronomy applications in the 100- to 2000-MHz frequency range. The high gain of the backfire is based on the high-amplitude standing-wave field distribution formed between two planar reflectors. The space between the reflectors acts like an open resonating cavity that in basic configuration and function resembles a Fabrey-Perot laser cavity. An S-band model of a 4.0-wavelength backfire produces a gain of 23.5 dB at its optimum frequency, which corresponds to the gain of an equal-size paraboloidal antenna of 60% efficiency. Patterns show a very low side- and backlobe level over a frequency range of 1.25 to 1. Design information for these backfire antennas is given. Compared with an optimized equal-length Yagi, the backfire antenna produces an increase in gain of more than 8 dB. To achieve a gain of this magnitude with an ordinary array, one of two recently built antennas for satellite applications uses 16 Yagis, each 2.0 wavelength long, to produce a gain of 22.4 dB, and another uses 36 cavity-backed slots to produce 21.2 dB. These results emphasize the advantages of the single-element backfire antenna, whose 23.5 dB gain is achieved through a simple structural design that does not depend on the complicated feed systems that are necessary components in multielement arrays. (Author).
Download or read book High gain UHF Backfire Antenna for Communications Telemetry and Radio Astronomy written by H. W. Ehrenspeck and published by . This book was released on 1967 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The backfire antenna described combines the structural advantages of a single endfire with the high gain of a reflector antenna. With its principal application in the gain range between 15 and 30 dB where ordinary endfire antennas become impractically long and paraboloidal antennas too expensive, it should prove to be especially advantageous for telemetry and radio astronomy applications in the 100- to 2000-MHz frequency range. The high gain of the backfire is based on the high-amplitude standing-wave field distribution formed between two planar reflectors. The space between the reflectors acts like an open resonating cavity that in basic configuration and function resembles a Fabrey-Perot laser cavity. An S-band model of a 4.0-wavelength backfire produces a gain of 23.5 dB at its optimum frequency, which corresponds to the gain of an equal-size paraboloidal antenna of 60% efficiency. Patterns show a very low side- and backlobe level over a frequency range of 1.25 to 1. Design information for these backfire antennas is given. Compared with an optimized equal-length Yagi, the backfire antenna produces an increase in gain of more than 8 dB. To achieve a gain of this magnitude with an ordinary array, one of two recently built antennas for satellite applications uses 16 Yagis, each 2.0 wavelength long, to produce a gain of 22.4 dB, and another uses 36 cavity-backed slots to produce 21.2 dB. These results emphasize the advantages of the single-element backfire antenna, whose 23.5 dB gain is achieved through a simple structural design that does not depend on the complicated feed systems that are necessary components in multielement arrays. (Author)
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1971 with total page 1330 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Instrumentation Papers written by and published by . This book was released on 1966 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microwave Cavity Antennas written by Akhileshwar Kumar and published by Artech House Antenna Library. This book was released on 1989 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Paraboloidal Reflector Antenna in Radio Astronomy and Communication written by Jacob W. M. Baars and published by Springer Science & Business Media. This book was released on 2007-07-16 with total page 270 pages. Available in PDF, EPUB and Kindle. Book excerpt: Radio astronomers have developed techniques of calibration of large reflector antennas with radio astronomical methods, but these have not been comprehensively described. This text aims to fill this gap, taking a practical approach to the characterisation of antennas. All calculations and results in the form of tables and figures have been made with Mathematica by Wolfram Research. The reader can use the procedures for the implementation of his own input data.
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:
Download or read book OAR Cumulative Index of Research Results written by and published by . This book was released on 1967 with total page 1264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NTC 69 Record written by and published by . This book was released on 1969 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Government Reports Annual Index written by and published by . This book was released on 1968 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of AFCRL Publications from 1 October to 31 December 1967 written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1968 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Bibliography of AFCRL Publications from 1 January to 31 March 1968 written by Air Force Cambridge Research Laboratories (U.S.) and published by . This book was released on 1968 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalog of the United States Geological Survey Library written by U.S. Geological Survey Library and published by . This book was released on 1974 with total page 732 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book U S Government Research and Development Reports Index written by and published by . This book was released on 1968 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings written by and published by . This book was released on 1969 with total page 342 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Papers and Discussions written by and published by . This book was released on 1969 with total page 596 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Modern Antenna Design written by Thomas A. Milligan and published by John Wiley & Sons. This book was released on 2005-07-11 with total page 646 pages. Available in PDF, EPUB and Kindle. Book excerpt: A practical book written for engineers who design and use antennas The author has many years of hands on experience designing antennas that were used in such applications as the Venus and Mars missions of NASA The book covers all important topics of modern antenna design for communications Numerical methods will be included but only as much as are needed for practical applications
