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Multiband Reconfigurable Filtering Monopole Antenna for Cognitive Radio Applications
IEEE Antennas and Wireless Propagation Letters, 2018A compact frequency-agile multiband filtenna is presented in this letter. The proposed reconfigurable filtering antenna performs independent switching between four operating bands viz.
Saffrine Kingsly +6 more
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On antennas for Cognitive Radios
2011 XXXth URSI General Assembly and Scientific Symposium, 2011Cognitive Radios (CR) are a concept of radios endowed with an intelligence that allows them to perceive changes in their environment and adapt their parameters to maintain a quality of Service (QoS). While the parameters concerned by the adaptation enclose theoretically all of those of a radio (modulation, coding, …etc.), it is certainly the change of ...
F. Ghanem, M. H. Rijal, P. S. Hall
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Introduction to radio and radio antennas
IEEE Spectrum, 1971Electromagnetic wave propagation is a simple and beautiful phenomenon, but its rigorous mathematical derivation from Maxwell's equations is formidable. This article makes many of the concepts visible and plausible using only mathematics available to college freshmen and taught today in most high schools.
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SAID Fiber-Antenna Radio Head at 50 GHz
European Microwave ConferencePlanar transmitting antennas with a direct photodiode (PD) connection for 50 GHz fiber-fed signal radiation are presented. The short asymmetrical inductive dipole (SAID) antenna enables independent adjustment of either the real and imaginary part of the ...
Sara Vega +7 more
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Trees performing as radio antennas
IEEE Transactions on Antennas and Propagation, 1975Radio transmission and reception experiments conducted in a tropical jungle are described. The performance of conventional whip antennas is compared with the performance of trees utilized as antennas in conjunction with hybrid electromagnetic antenna couplers (HEMAC's). The trees were found to outperform the whip in some cases by up to 20 dB.
K. Ikrath, W. Kennebeck, R. Hoverter
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Radio-Telescope Antenna Parameters
IEEE Transactions on Military Electronics, 1964Principal antenna parameters which are useful in characterizing the electrical performance of radio-telescope antennas are defined and the relations between them are established. The application of these parameters to radio astronomical measurements is discussed.
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A UWB Antenna for Impulse Radio
2006 IEEE 63rd Vehicular Technology Conference, 2006A UWB antenna, which is adopted from a ground penetrating radar (GPR) antenna, is proposed for impulse radio application. The antenna has dimensioning of 7 cm by 1.5 cm and is based on a modified bow-tie structure. It employs improved resistive loading for transmission of 0.2-ns monocycles with minimal ringing.
A.A. Lestari +3 more
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2009 Applied Electromagnetics Conference (AEMC), 2009
Radio Astronomy has made very significant contributions to human knowledge by discovering such exotic phenomena as quasars, pulsars, active galactic nuclei, superluminal motion and cosmic microwave background. These have been possible by the ever increasing sensitivity and angular resolution of the radio telescopes over the last six decades.
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Radio Astronomy has made very significant contributions to human knowledge by discovering such exotic phenomena as quasars, pulsars, active galactic nuclei, superluminal motion and cosmic microwave background. These have been possible by the ever increasing sensitivity and angular resolution of the radio telescopes over the last six decades.
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Directional antennas and radio networks
2009 IEEE International Conference on Microwaves, Communications, Antennas and Electronics Systems, 2009Spectrum management (SM) is a well known important issue [1]. Demand for RF spectrum already exceeds supply [2]. The advent of cognitive radio functionality and other SM advances, while important, have actually been constrained by an almost exclusive focus on omni-directional antennas, with scant attention paid to the spectrum deconfliction benefits ...
Newton Love +2 more
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The Antennas for Mobile Radio Communications
31st European Microwave Conference, 2001, 2001The results of new two-frequency two-vibrator radiators researches are presented. It is shown that under certain ratios of operational frequencies there is a current cut-off effect between vibrators that provides optimum quasiisotropic patterns.
A. Krjukov, V. Ovsyanikov
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