Results 281 to 290 of about 68,865 (333)
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High-directivity antenna with small antenna aperture
Applied Physics Letters, 2009We show in this letter that, by using an inhomogeneous metamaterial shell, it is possible to achieve highly directive emission with a small antenna aperture. The material parameters of the metamaterial substrate are obtained by a nonmonotonic optical transformation.
Yu Luo +4 more
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4th International Conference on Antenna Theory and Techniques (Cat. No.03EX699), 2004
Using quite general concepts as guidance in the design of an antenna for short pulse transmission and reception, a new type of horn-antenna has been devised. A certain variety of experimental data obtained by the antenna are presented.
Titov, A. N., Titov, A. A.
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Using quite general concepts as guidance in the design of an antenna for short pulse transmission and reception, a new type of horn-antenna has been devised. A certain variety of experimental data obtained by the antenna are presented.
Titov, A. N., Titov, A. A.
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Precision direction finding antennas
IEEE Transactions on Consumer Electronics, 1990A compact and precise direction finding antenna was designed by combining a monopole and a loop antenna. A cardioid radiation pattern was achieved and, in particular, a sharp null is obtained. The antenna is useful for tracking and locating the target when the operator is within a couple of hundred meters of the target. The construction of this antenna
S. Le-Ngoc, T. Le-Ngoc
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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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Directive photonic-bandgap antennas
IEEE Transactions on Microwave Theory and Techniques, 1999This paper introduces two new photonic bandgap (PBG) material applications for antennas, in which a photonic parabolic reflector is studied. It is composed of dielectric parabolic layers associated to obtain a PBG material. The frequency gap is used to reflect and focus the electromagnetic waves.
M. Thevenot +3 more
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Directed Circular Polarized Antenna
2018 XXIIIrd International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED), 2018The goal of proposed research is to construct the circular polarized narrow-band directed antenna using low-loss dielectric and high relative permittivity material for the substrate. Presented first part contains the simulation of such antenna using the software which based on Finite Element Method for the purpose to fined optimal parameters of such ...
V. Barbakadze +3 more
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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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Directivity of planar antennas
IEEE Antennas and Propagation Magazine, 1999Starting with a common formula for directivity, given beamwidths, the author gives the modifications needed to improve the accuracy when the distribution is known. Also included is a nomograph that shows the parameters of the Taylor single-parameter distribution, and allows trade studies versus the sidelobe level.
V. Schejbal, J.D. Mahoney, N. McDonald
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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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Directional antenna for radiomodems
13th International Crimean Conference Microwave and Telecommunication Technology, 2003. CriMiCo 2003., 2003A reflector antenna for digital data transmission systems using 2.4...2.485 GHz radiomodems has been designed. The SWR, input impedance and directional characteristics have been calculated. Experimental studies of the antenna are described.
A.A. Savochkin +2 more
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