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Antenna architecture of a nano-satellite for Radio Astronomy
2014 IEEE Aerospace Conference, 2014Recent technological advancements have led to the emergence of a new miniaturized satellite platforms and this opened up the path for a whole new range of applications. The Orbiting Low Frequency Antennas for Radio Astronomy (OLFAR) project is one of these applications, and aims to develop a low-frequency radio telescope for the 0.3 MHz to 30 MHz band.
Budianu, A. +4 more
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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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IEEE Antennas and Propagation Society Newsletter, 1976
Describes the special features, technology, applications and design of the Arecibo radio antenna.
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Describes the special features, technology, applications and design of the Arecibo radio antenna.
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Radio Channel Fundamentals and Antennas
2014In this chapter, we begin by discussing the fundamentals of the radio channel. Typical Radio Transmitter and Receiver block diagrams are reviewed, together with the components of a wireless communications system. Then, we turn to addressing the phenomenon of wave propagation, in particular, Multi-Path Propagation, Free-Space, and Path Loss.
Héctor J. De Los Santos +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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On geometry of radio antenna placements
1998A smooth planar curve \(x(t)\) is said to have unique differences if all the vectors \(x(t)- x(t')\) that correspond to different pairs \((t,t')\), \(t\neq t'\), are different. In this note it is proved that if a smooth planar curve has unique differences, then it is a convex curve.
Kosheleva, Olga +3 more
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Radio Astronomy Antennas by the Thousands
Experimental Astronomy, 2004Large number of microwave antennas of size and surface accuracy appropriate for the Square Kilometre Array (SKA) have not been manufactured previously. To minimize total cost, the design needs to be much more carefully considered and optimized than would be affordable for a small number of antennas.
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Wideband antennas for radio astronomy
2006 First European Conference on Antennas and Propagation, 2006The global radio astronomy community has for the last several years embarked on an exciting project known as Square Kilometer Array (SKA). This project is a radio telescope operational from 0.1GHz to 25GHz, with a square kilometer of overall collecting area, providing an increase in sensitivity of two orders of magnitude.
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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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