Results 251 to 260 of about 630,146 (307)
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2017
This chapter reports design and analysis methods for planar antennas based on modulated metasurfaces (MTSs). These antennas transform a surface wave (SW) into a leaky wave by means of the interaction with a MTS having a spatially modulated equivalent impedance.
Minatti, Gabriele +9 more
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This chapter reports design and analysis methods for planar antennas based on modulated metasurfaces (MTSs). These antennas transform a surface wave (SW) into a leaky wave by means of the interaction with a MTS having a spatially modulated equivalent impedance.
Minatti, Gabriele +9 more
openaire +3 more sources
Optical Antenna Gain 2: Receiving Antennas
Applied Optics, 1974Expressions are derived for the gain of a centrally obscured, circular optical antenna when used as the collecting and focusing optics in a laser receiver which include losses due to (1) blockage of the incoming light by the central obscuration, (2) the spillover of energy at the detector, and (3) the effect of local oscillator distribution in the case
J J, Degnan, B J, Klein
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Optical Antenna Gain 1: Transmitting Antennas
Applied Optics, 1974The gain of centrally obscured optical transmitting antennas is analyzed in detail. The calculations, resulting in near- and far-field antenna gain patterns, assume a circular antenna illuminated by a laser operating in the TEM(00) mode. A simple polynomial equation is derived for matching the incident source distribution to a general antenna ...
B J, Klein, J J, Degnan
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Nano Letters, 2012
We experimentally demonstrate the directional emission of polarized light from single semiconductor nanowires. The directionality of this emission has been directly determined with Fourier microphotoluminescence measurements of vertically oriented InP nanowires.
Grzela, G. +5 more
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We experimentally demonstrate the directional emission of polarized light from single semiconductor nanowires. The directionality of this emission has been directly determined with Fourier microphotoluminescence measurements of vertically oriented InP nanowires.
Grzela, G. +5 more
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Spiral antennas and antenna arrays
2005 IEEE Antennas and Propagation Society International Symposium, 2005The planar square-Archimedean spiral located at the center of a dipole has been demonstrated as a valuable passive antenna element in the upper MM-wave and THz regions between about 100 GHz and 2 THz (Bjarnason, E. et al., Appl. Phys. Lett., vol.85, p.3983, 2004).
R.M. Bilotta, E.B. Brown
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2021
The capability of controlling the spatial broadening of the radiation moving away from the relevant sources is considered a very attractive feature for a plethora of applications, such as imaging, diagnostic, and wireless power transfer. An important class of ideal solutions of the scalar wave equation that remain confined and do not undergo ...
Comite, Davide +4 more
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The capability of controlling the spatial broadening of the radiation moving away from the relevant sources is considered a very attractive feature for a plethora of applications, such as imaging, diagnostic, and wireless power transfer. An important class of ideal solutions of the scalar wave equation that remain confined and do not undergo ...
Comite, Davide +4 more
openaire +2 more sources
Large antennas and microwave antennas
2005Large antennas and microwave antennas, which form the subject of the remaining chapters of this book, are characterized by the property that their useful dimensions are very large compared with the wavelength involved. The word ‘large’ refers to the physical dimensions of the antenna (radio telescopes, for example) compared with which the wavelengths ...
S. Drabowitch +4 more
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Antenna Analyses: Objects Near Antennas and Microstrip Antennas.
1980Abstract : In this report the research work encompassed two classes of antenna analyses. One was an investigation of the effects of a nearby object upon an antenna and its performance and the other was a study of the center-fed, circular microstrip antenna.
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Multiple antennas: smart antenna systems
2010Introduction Wireless channels suffer from time-varying impairments such as multipath fading, interference, and noise. Diversity, such as time, frequency, space, polarization, or angle diversity, is typically used to mitigate these impairments. Diversity gain is achieved by receiving independent-fading replicas of the signal.
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Cosmology with the Laser Interferometer Space Antenna
Living Reviews in Relativity, 2023Germano Nardini
exaly