Results 261 to 270 of about 14,576 (298)
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Employing Directional Antennas in Double-Directional Radio Channel
2005 2nd International Symposium on Wireless Communication Systems, 2005A novel scheme that jointly utilizes switched beam antennas in double-directional radio channel (DDRC) is proposed. Employing directional beam pattern at both transmitter (Tx) and receiver (Rx) sides in DDRC provides distributed directivity gain (DDC). Jointly switching directional patterns at both ends provides extra diversity gain.
Chen Sun +2 more
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Directivity of omnidirectional antennas
IEEE Antennas and Propagation Magazine, 1993A graph describing the directivity of an omnidirectional antenna versus the half-power elevation-plane beamwidth is presented. This data has been calculated assuming a sin/sup n/ theta elevation-plane pattern. A closed-form curve-fitted approximation for this relationship is also presented. >
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The directional coupler antenna
IRE International Convention Record, 2005The combination of four broadband 3 db directional couplers and four radiating elements into an antenna for direction-finding purposes has been investigated. Under theoretical conditions, two overlapping beams with constant crossover level and variable crossover slope over an infinite frequency band can be obtained.
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1988
The purpose of a radio direction finder (df) is to measure the direction of arrival of a radio signal. Traditionally the azimuth angle of arrival, i.e., the angle of arrival in the horizontal plane, has been considered sufficient to define the ...
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The purpose of a radio direction finder (df) is to measure the direction of arrival of a radio signal. Traditionally the azimuth angle of arrival, i.e., the angle of arrival in the horizontal plane, has been considered sufficient to define the ...
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Directional antennas standardization
Proceedings of International Symposium on Electromagnetic Compatibility ELMAGC-97, 1997In the literature and internationally accepted standardization procedures the problem of directional antennas standardization in the frequency range below 1 GHz still has not been satisfactorily solved. The applicability of a typical standard receiving antenna method for this purpose is being considered.
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1992
This chapter discussed the direction finding antennas having two classes to distinguish this. These are (i) Terrestrial or airborne types requiring omniazimuth but limited elevation coverage (ii) Systems for tracking space vehicles and radio stars where essentially hemispherical coverage is required.
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This chapter discussed the direction finding antennas having two classes to distinguish this. These are (i) Terrestrial or airborne types requiring omniazimuth but limited elevation coverage (ii) Systems for tracking space vehicles and radio stars where essentially hemispherical coverage is required.
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Directivity and the Antenna Beam
1998In this chapter, the author discusses how the energy radiated by an antenna is distributed in angle and examine the salient characteristics of the radiation pattern - beamwidth, gain, and sidelobes. It was then shown how the sidelobes may be reduced; how fast, versatile beam positioning may be accomplished with electronic scanning; and how high angular
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All-metamaterial-based subwavelength cavities (λ∕60) for ultrathin directive antennas
Applied Physics Letters, 2006Andre De Lustrac
exaly