Results 241 to 250 of about 85,808 (303)

Microwave antenna holography

IEEE Transactions on Microwave Theory and Techniques, 1992
The application of the holography technique to the newly constructed NASA/JPL Deep Space Network (DSN) 34-m beam-waveguide antenna, resulting in 4.1-dB performance improvement at 32 GHz by reducing the main reflector RMS surface error at 0.43 mm, is described.
D.J. Rochblatt, B.L. Seidel
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Large antennas and microwave antennas

2005
Large antennas and microwave antennas, which form the subject of the remaining chapters of this book, are characterized by the property that their useful dimensions are very large compared with the wavelength involved. The word ‘large’ refers to the physical dimensions of the antenna (radio telescopes, for example) compared with which the wavelengths ...
S. Drabowitch, A. Papiernik, H. D. Griffiths, J. Encinas, B. L. Smith   +4 more
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Microwave Antenna Measurements

Proceedings of the IRE, 1947
A description is given of the techniques involved in measuring the properties of microwave antennas. The measuring methods which are peculiar to these frequencies are discussed, and include the measurement of gain, beam width, minor lobes, wideangle radiation, mutual coupling between antennas, phase, and polarization.
C.C. Cutler, A.P. King, W.E. Kock
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Microwave Radiation Hazards around Large Microwave Antenna

American Industrial Hygiene Association Journal, 1973
The microwave radiation hazards associated with the use of large antennas become increasingly more dangerous to personnel as the transmitters go to ever higher powers. The near field area is of the greatest concern,, It has spill over from sub-reflector and reflections from nearby objects. Centimeter waves meeting in phase will reenforce each other and
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Microwave Antenna Technology

16th European Microwave Conference, 1986, 1986
Recent microwave antenna technologies which are developed in Japan are reviewed. Main antennas which are practically used in various fields are described. The trends of antenna research works are also shown.
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A microwave antenna lead

Instruments and Experimental Techniques, 2013
A microwave antenna lead for feeding signals to high-voltage electrodes is described. The unit includes the receiving and transmitting microwave antennas, separated by a high-voltage insulator. The antennas are made as two symmetrical parts of a cut-across half-wavelength coaxial closely coupled resonator, and the insulator is made as a ceramic disk ...
A. M. Barnyakov, V. I. Ivannikov, A. E. Levichev, V. M. Pavlov, Yu. D. Chernousov, I. V. Shebolaev   +5 more
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Microwave ferroelectric antenna arrays

Proceedings of the 2001 SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference. (Cat. No.01TH8568), 2002
In this paper, theoretical investigation of ferroelectric antenna arrays without phase shifters and attenuators has been presented. This concept is based on utilizing a voltage-controlled ferroelectric array, where the variable pattern of each antenna element is used to shape the array pattern.
J. Modelski, Y. Yashchyshyn
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Deployable microwave lens antennas

Proceedings, IEEE Aerospace Conference, 2003
Because of their large mass, waveguide lens antennas have not been widely used in space, in spite of their established superiority to reflector antennas for many aerospace applications. This paper introduces the concept of fabrication of lightweight waveguide lenses using thin, metallized polymer sheets.
M. Hamidi, J. Withington, E. Wiswell
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Microwave Omnidirectional Antennas

Proceedings of the IRE, 1947
This paper describes briefly a number of radiating elements which have proved useful in the design of high- and low-gain omnidirectional antennas at wavelengths of 3 and 10 centimeters.
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Microwave Antennas and Dielectric Surfaces

Journal of Applied Physics, 1949
For a plane dielectric sheet near a receiving antenna the power varies sinusoidally with distance, having a half-wave period and an average proportional to the transmission coefficient. This is explained by assuming an equivalent antenna reflection, an assumption checked by special experiments.
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