Results 181 to 190 of about 14,034 (233)
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Multibeam and multipolarization antenna
2006 First European Conference on Antennas and Propagation, 2006The design of a novel reconfigurable antenna for MIMO systems is presented. Simulation and experimental results shows its capabilities in a multibeam reconfiguration in a 4? steradians environment. It can allow an enhancement in wireless communication employing multipath channel combining with a radiation pattern diversity.
Sarrazin, Julien +3 more
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IEEE Antennas and Propagation Society International Symposium. Digest. Held in conjunction with: USNC/CNC/URSI North American Radio Sci. Meeting (Cat. No.03CH37450), 2004
One of the most difficult problems in scanning antenna technology is the realization of wide angle scanning. The proposed architecture seems to overcome the difficulties of realizing complex antennas, and offers high efficiency with wide-angle scanning capabiliy and with (almost) indentical beams regardless of scanning angle.
Herscovici, Naftali, Šipuš, Zvonimir
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One of the most difficult problems in scanning antenna technology is the realization of wide angle scanning. The proposed architecture seems to overcome the difficulties of realizing complex antennas, and offers high efficiency with wide-angle scanning capabiliy and with (almost) indentical beams regardless of scanning angle.
Herscovici, Naftali, Šipuš, Zvonimir
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Multibeam Antenna in Millimeter Waves
32nd European Microwave Conference, 2002, 2002This paper deals with a multibeam antenna in 60 GHz band. This structure is based on a Butler Matrix which fed a four printed antenna array. Two different solutions are presented to avoid the crossing point of the microstrip line : a microstrip-thick slot-microstrip transition or two hybrids 90°.
Lafond, Olivier, Himdi, Mohamed
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Multibeam coupling in photorefractive SBN:Ce
Optics Letters, 1988Theoretical and experimental results are presented for simultaneous multibeam coupling in photorefractive SBN:Ce. Within a single crystal, multiple signals are amplified through a coupling process that employs a single pump. The coupling gain of each signal results from coupling both between the pump and the signal and between different signals.
J, Ma +5 more
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Scheduling in Multibeam Satellites with Interfering Zones
IEEE Transactions on Communications, 1983In this paper we study the traffic scheduling problem in an SS/TDMA system with interfering beams. We investigate a twostep approach, the first step being the assignment of orthogonal polarization to reduce the interference, and the second step being the scheduling of traffic, taking into account the "resultant" interference. The first step we show can
GOPAL IS +2 more
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Multiuser decoding for multibeam systems
IEEE Transactions on Vehicular Technology, 2000An iterative multiuser decoding algorithm for co-channel BPSK/QPSK users in a multibeam system is presented. The approach can be applied to the return link of multibeam satellites and to terrestrial systems with sectored base-station antennas. It allows the reuse of the same spectrum in each beam.
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Journal of the Structural Division, 1969
Simply supported multibeam bridges with elements of solid or box section are considered. The structure is idealized as a series of discrete beams, which may include edge beams, joined by longitudinal hinges. The structure is analyzed by a computer-oriented direct flexibility technique, using harmonic analysis to reduce the two-dimensional problem to a ...
Graham H. Powell +2 more
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Simply supported multibeam bridges with elements of solid or box section are considered. The structure is idealized as a series of discrete beams, which may include edge beams, joined by longitudinal hinges. The structure is analyzed by a computer-oriented direct flexibility technique, using harmonic analysis to reduce the two-dimensional problem to a ...
Graham H. Powell +2 more
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A Multibeam Cassegrain Antenna
1975 5th European Microwave Conference, 1975This paper deals with generation of a multibeam pattern for three-dimensional radar surveillance by a stacked feed horn system installed in a Cassegrain antenna. Although its effective f/D-ratio is relatively high compared with the corresponding one of the primarily feed paraboloid, lateral displacement of feed horns in the focal plane results in ...
H. Gniss, E. Zocher
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1969 International Electron Devices Meeting, 1969
CRT devices, both for photorecording and real time display applications, can be improved in certain of their characteristics by utilizing a number of electron beams simultaneously modulated in the tube. A plurality of beams, when properly generated, focused and deflected, will display information with writing speed, video band-width and brightness ...
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CRT devices, both for photorecording and real time display applications, can be improved in certain of their characteristics by utilizing a number of electron beams simultaneously modulated in the tube. A plurality of beams, when properly generated, focused and deflected, will display information with writing speed, video band-width and brightness ...
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2017
Multibeam echosounders have revolutionized our ability to resolve seabed geomorphology and regionally define its substrate. Using a fan of narrow acoustic beams, the slant ranges, angles and returned backscattered intensity can be employed to define the seabed elevation and infer the substrate.
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Multibeam echosounders have revolutionized our ability to resolve seabed geomorphology and regionally define its substrate. Using a fan of narrow acoustic beams, the slant ranges, angles and returned backscattered intensity can be employed to define the seabed elevation and infer the substrate.
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