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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An electromechanical calculator for horizontal patterns of multi-element antennas

Harriman, Dean Emerson 08 1900 (has links)
No description available.
2

Some aspects of the problem of phase errors in paraboloidal reflector antennas

Vu, The Bao January 1966 (has links)
Ph.D. thesis 1968 from the Dept. of Electrial Engineering, University of Adelaide / 156 leaves : ill., graphs / Title page, contents and abstract only. The complete thesis in print form is available from the University Library.
3

Design of multihop packet radio networks.

January 1985 (has links)
by Hung Kwok Wah. / Summary in Chinese and English / Bibliography: leaves 43-46 / Thesis (M.Ph.)--Chinese University of Hong Kong, 1985
4

Multi-antenna and receiver slotted ALOHA packet radio systems with capture

Lau, Chiew Tong January 1990 (has links)
The problem of data transmission in a packet radio system with one central base station and a number of mobile/stationary terminals is addressed. More specifically, the effects of possible collisions between packets on the inbound channel are investigated. Schemes which can be used to improve the performance are studied. The use of capture to improve the performance of slotted ALOHA systems is discussed. For a power group division scheme proposed by Metzner in which a capture effect is artificially induced, it is shown that in the two power group case, the higher power packet needs only be able to tolerate interference from up to three lower power packets in order to realize most of the achievable improvement of the infinite capture model. The evaluation of the performance for more than two power groups is also considered. A packet radio system in which a capture effect exists due to the fact that mobiles will generally be at different distances from the base station is also investigated. A number of different capture and spatial distribution models are discussed. Methods for evaluating the probability [formula omitted] of successful reception when there are [formula omitted] contending transmitters are examined. It is shown that a generalized capture model can be used to estimate [formula omitted] for an example system which uses non-coherent frequency shift keying modulation. This model can be applied to other systems as well. In most practical systems, the mobiles cannot get arbitrarily close to the base station. The effects of this constraint on [formula omitted] is examined. The dependence of the capture probability for a test mobile on its distance from the base station is also analyzed. The use of multiple directional antennas and receivers in a slotted ALOHA system in which the signals from the different transmitters are received with more or less the same powers is analyzed. It is shown that the performance of the system can be substantially improved by using directional antennas and multiple receivers. Results indicate that fewer than five antennas per receiver are required in order to achieve most of the achievable performance. A finite population Markov model is used to evaluate the performance of a multi-antenna and receiver slotted ALOHA system in a mobile radio environment in which the signal power levels from different mobiles are no longer equal. The effects of three different antenna patterns, background noise and Rayleigh fading are studied. Here again, numerical results indicate that substantial gains are possible with the use of several antennas and receivers. It is also found that the dynamic behaviour of the system is improved. The selection of the antennas to be connected to the receivers becomes an issue if the number of receivers at the base station is less than the number of antennas . Four antenna selection schemes are compared for three different channel models, assuming an ideal antenna pattern. It is found that the scheme which selects the antennas with the largest received signal powers is nearly optimum. The effects of using a more practical non-ideal antenna pattern are also discussed. / Applied Science, Faculty of / Electrical and Computer Engineering, Department of / Graduate
5

RADIO DIRECTION FINDING AND THE ADCOCK ANTENNA.

Roleson, Willaim Scott. January 1982 (has links)
No description available.
6

The principal features of long Yagi antennas and methods of obtaining maximum gain

Kalelioglu, Cevdet, 1930- January 1961 (has links)
No description available.
7

Radiation characteristics of vehicle-mounted antennas and their application to comprehensive system design.

Kubina, Stanley James January 1972 (has links)
No description available.
8

Characterization of the effects of the human head on communication with implanted antennas /

Pecoraro, Michael A. January 2010 (has links)
Thesis (M.S.)--Rochester Institute of Technology, 2010. / Typescript. Includes bibliographical references (leaves 110-114).
9

Radiation characteristics of vehicle-mounted antennas and their application to comprehensive system design.

Kubina, Stanley James January 1972 (has links)
No description available.
10

Null and beam steering performance of rectanglar arrays with Dolph-Chebyshev weighting /

Hemmati, Varahram. January 1900 (has links)
Thesis (M.App.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 92-94). Also available in electronic format on the Internet.

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