Results 31 to 40 of about 1,103,532 (303)
Radiation pattern of a classical dipole in a photonic crystal: photon focusing
, 2003 The asymptotic analysis of the radiation pattern of a classical dipole in a photonic crystal possessing an incomplete photonic bandgap is presented. The far-field radiation pattern demonstrates a strong modification with respect to the dipole radiation ...
A. A. Maradudin +14 more
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The Radiation Pattern on an Ultrasonic Focusing Radiator [PDF]
The Journal of the Acoustical Society of America, 1947 A focusing quartz radiator made in the form of a concave-convex lens of constant thickness (and being X-cut on the axis) should radiate spherical sound waves which focus at the center of curvature of the radiator surfaces. Because of wave diffraction, the focus should deviate from infinitely sharp in the same manner as is well known in the optical ...
openaire +1 more source
Plant Foliar Geometry as a Biomimetic Template for Antenna Design
Biomimetics, 2023 Plant diversity includes over 300,000 species, and leaf structure is one of the main targets of selection, being highly variable in shape and size. On the other hand, the optimization of antenna design has no unique solution to satisfy the current range ...
Jose Ignacio Lozano +5 more
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Radiation from elementary sources in a uniaxial wire medium
, 2012 We investigate the radiation properties of two types of elementary sources embedded in a uniaxial wire medium: a short dipole parallel to the wires and a lumped voltage source connected across a gap in a generic metallic wire. It is demonstrated that the
J. Brown +6 more
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Физика волновых процессов и радиотехнические системыBackground. Antenna arrays are widely used in a variety of modern radio engineering systems for wireless communication and radar. The phenomenon of mutual coupling of antenna elements, which is manifested in practical implementation, may cause noticeable
Anatoly M. Bobreshov +4 more
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Calculation of radiation patterns
Electronics Letters, 1969 The letter proves that two distinct methods of calculating the radiation pattern of a spherical-aperture distribution are mathematically equivalent, i.e. by a spherical-harmonic expansion or by Silver's far-field formula. The merits of each method and their extension to arbitrary-shaped apertures are briefly discussed.
J.R. James, L.W. Longdon
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Patterns of the radiation properties for Peano antennas
Scientific Reports, 2023 AbstractThis paper studies metallic microstrip antennas with air as a substrate in the UHF band, patterned after space-filling, self-avoiding, and self-similar (FASS) Peano curves. Our novel study is based on context-free grammar and genetic programming as computing tools to unravel the role of geometry on both; the Voltage Standing Wave Ratio (VSWR ...
René Pérez-Moroyoqui +2 more
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Microstrip Patch Antenna for GNSS Applications
Applied SciencesThis research paper presents the results of an analysis conducted on a microstrip patch antenna designed to operate within the 1.559–1.591 GHz frequency band, which encompasses three major satellite constellations: GPS, Galileo and BeiDou.
Hatice-Andreea Topal +1 more
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Физика волновых процессов и радиотехнические системы, 2019 The apertures amplitude-phase distribution of a linear antenna array, ensuring the formation of frequency-independent direction-finding characteristics in a wide frequency band, is considered.
N.I. Bobkov +2 more
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Optical Scattering of Liquid Gallium Nanoparticles Coupled to Thin Metal Films
Nanomaterials, 2020 We investigate experimentally and numerically the scattering properties of liquid gallium nanoparticles coupled to a thin gold or silver film. The gallium nanoparticles are excited either directly by using inclined white light or indirectly by surface ...
Fu Deng +4 more
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