Results 21 to 30 of about 537,168 (232)

Power Profile-Based Antenna Selection for Millimeter Wave MIMO With an All-Planar Lens Antenna Array

IEEE Access, 2021
Lens antenna arrays can significantly reduce the number of radio frequency (RF) chains and provide a cost-effective beamforming approach to millimeter-wave massive multiple-input multiple-output (MIMO) systems.
Qianyun Zhang, Xinwei Li, Lei Cheng, Yuanwei Liu, Yue Gao   +4 more
doaj   +1 more source

Metamaterials for light rays: ray optics without wave-optical analog in the ray-optics limit [PDF]

, 2009
Volumes of sub-wavelength electromagnetic elements can act like homogeneous materials: metamaterials. In analogy, sheets of optical elements such as prisms can act ray-optically like homogeneous sheet materials.
Hamilton, A.C., Courtial, J.
core   +1 more source

An Electromagnetic Sensor with a Metamaterial Lens for Nondestructive Evaluation of Composite Materials

Sensors, 2015
This paper proposes the study and implementation of a sensor with a metamaterial (MM) lens in electromagnetic nondestructive evaluation (eNDE). Thus, the use of a new type of MM, named Conical Swiss Rolls (CSR) has been proposed.
Adriana Savin, Rozina Steigmann, Alina Bruma, Roman Šturm   +3 more
doaj   +1 more source

Analysis of the influence of dispersion of metamaterials in a cylindrical Luneberg lens with extended focus

Физика волновых процессов и радиотехнические системы, 2020
Cylindrical Lunebeg lenses allow azimuthal scanning in a wide sector of angles. The article discusses a cylindrical Luneberg lens with an out-of-focus parallel printed circuit boards made of thin fiberglass (FR-4) with an etched H-shaped metamaterial ...
Yuri G. Pasternak, Evgeny A. Rogozin, Ruslan E. Rogozin, Sergei M. Fedorov   +3 more
doaj   +1 more source

Metamaterial Lenses and Their Applications at Microwave Frequencies

Advanced Photonics Research, 2021
Metamaterials (MTMs) are artificial structures characterized by flexible and designable electromagnetic (EM) properties, including permittivity, permeability, and refractive index.
Wenxuan Tang, Jia Chen, Tie Jun Cui
doaj   +1 more source

Tight focusing field of cylindrical vector beams based on cascaded low-refractive index metamaterials

Nanophotonics, 2023
Using low-refractive-index metamaterials, we design a transmission-type radial-angular cylindrical vector beam generator. A high numerical aperture lens is constructed using an asymmetric meta-grating structure. The metamaterial vector beam generator and
Ke Lan, Li Chenxia, Zhang Simeng, Fang Bo, Tang Ying, Hong Zhi, Jing Xufeng   +6 more
doaj   +1 more source

Past, present and future of seismic metamaterials: experiments on soil dynamics, cloaking, large scale analogue computer and space–time modulations

Comptes Rendus. Physique, 2021
Some properties of electromagnetic metamaterials have been translated, using some wave analogies, to surface seismic wave control in sedimentary soils structured at the meter scale.
Brûlé, Stéphane, Guenneau, Sébastien
doaj   +1 more source

Bianisotropic Effective Parameters of Optical Metamagnetics and Negative-Index Materials [PDF]

, 2011
Approaches to the adequate homogenization of optical metamaterials are becoming more and more complex, primarily due to an increased understanding of the role of asymmetric electrical and magnetic responses, in addition to the nonlocal effects of the ...
Joshua D. Borneman, Vladimir M. Shalaev, Drachev, Vladimir P., Xingjie Ni, Borneman, Joshua D., Vladimir P. Drachev, Kildishev, Alexander V., Ni, Xingjie, Shalaev, Vladimir M., Alexander V. Kildishev   +9 more
core   +1 more source

Beam steering performance of compressed Luneburg lens based on transformation optics

Results in Physics, 2018
In this paper, two types of compressed Luneburg lenses based on transformation optics are investigated and simulated using two different sources, namely, waveguides and dipoles, which represent plane and spherical wave sources, respectively.
Ju Gao, Cong Wang, Kuang Zhang, Yang Hao, Qun Wu   +4 more
doaj   +1 more source

Study of a hemispherical metamaterial lens made of parallel printed circuit boards with metal diffusers of small electrical dimensions

Физика волновых процессов и радиотехнические системы, 2021
Antenna systems based on hemispherical lenses allow full azimuth scanning or electronically controlled sector scanning. The article presents a numerical simulation of a broadband multi-beam antenna system based on a hemispherical metamaterial lens made ...
Yuri G. Pasternak, Vladimir A. Pendyurin, Ruslan E. Rogozin, Sergei M. Fedorov   +3 more
doaj   +1 more source