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Showing 1 to 13 of 13 for “"antenna measurements"”.
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UAV-based Far-Field and Near-Field Antenna Measurements
L'abstract è presente nell'allegato / the abstract is in the attachment
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Antenna design using optimization techniques over various computaional electromagnetics. Antenna design structures using genetic algorithm, Particle Swarm and Firefly algorithms optimization methods applied on several electromagnetics numerical solutions and applications including antenna measurements and comparisons
… computation time, constraints put forward for antenna requirements and demand for large computer memory, are very common in the analysis due to the increased interests in tackling high-scale, more complex and higher-dimensional problems. On the other side, demands for even more accurate results …
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Antenna design using optimization techniques over various computaional electromagnetics. Antenna design structures using genetic algorithm, Particle Swarm and Firefly algorithms optimization methods applied on several electromagnetics numerical solutions and applications including antenna measurements and comparisons
… computation time, constraints put forward for antenna requirements and demand for large computer memory, are very common in the analysis due to the increased interests in tackling high-scale, more complex and higher-dimensional problems. On the other side, demands for even more accurate results …
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An investigation of series LC resonant circuits within a sleeve balun to achieve wideband operation
In antenna measurements, it is not recommended to connect a balanced antenna directly to the coaxial cable feed. A balun is required to prevent surface current from flowing onto the outer shield of the feed cable. Balun chokes like the sleeve balun, also known as bazooka balun or quarter-wavelength …
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Time domain antenna pattern measurements
Multipath on far-field antenna ranges causes distortion of antenna pattern measurements: The multi path components have differing path lengths and hence can be separated by illuminating the antenna under test with short-duration pulses. Alternatively, antenna measurements can be made in the …
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Energy storage in reconfigurable antennas
… potential performance advantages, reconfigurable antennas have seen limited use in mobile devices. These complicated antennas can be challenging to design, especially when the structure is electrically small or mid-sized. With small elements, finite groundplanes, and switches or reactive tuning …
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Measurement of Antenna Performance in Analog LMR Systems Using PL Tone Analysis
We are interested in measuring the in situ antenna performance in analog land mobile radio (LMR) FM systems. The gain (efficiency and directivity) and self-impedance of an antenna sufficiently characterize its performance and a number of traditional methods exist to measure these quantities. …
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Integral Identities for Passive Systems and Spherical Waves in Scattering and Antenna Problems
… limitations within electromagnetic theory and antenna theory have received significant attention in the last few years. However, the derivations are often relying on application specific and sometimes unsupported assumptions, and therefore a mathematically rigorous and generally applicable …
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Retrieval of Free Space Radiation Patterns through Measured Data in a Non-Anechoic Environment
<p>Antenna pattern measurements are usually carried out in an anechoic chamber. However, a good anechoic chamber is very expensive to construct. Previous research has attempted to compensate for the effects of extraneous fields measured in a non-anechoic environment to obtain a free space pattern …
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Radio-Frequency Plasma Expansion in Different Magnetic Nozzle Configurations
This thesis presents the first measurements conducted in the novel radio-frequency plasma device Moa. The research focuses on the effects of magnetic field strength and orientation on plasma expansion and ion acceleration when the location of plasma excitation is decoupled from the magnetic nozzle …
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Fluctuation-induced interactions and nonlinear nanophotonics
… new technique for determining Casimir forces via antenna measurements in tabletop experiments. This technique is based on a (derived) correspondence between the complex-frequency deformation of the Casimir frequency-integrand for any given geometry and the real-frequency classical electromagnetic …
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Antenna systems research
… is an overview of a number of investigations on antenna systems and related subjects over a period of 28 years, which has resulted in 44 publications in the technical literature, one current patent, and an M.Sc. thesis. The investigations have been grouped into 7 categories: - Log periodic …
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Contribution to the uncertainty evaluation in the measurement of the main antenna parameters = Contribución a la evaluación de la incertidumbre en la medida de los principales parámetros de antena
… polarization techniques and swept-frequency measurements, indirect measurements of antenna characteristics and automated test systems. The accurate determination of a physical quantity or performance by measurements is a challenging task. For microwave antennas there are some established …