Browsing by Subject "Millimeter wave devices"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    ItemOpen Access
    Millimeter-wave scale metamaterials
    (IEEE, 2009-11) Alıcı, Kamil Boratay; Özbay, Ekmel
    We review two metamaterial configurations, which are operating at the millimeter-wave scale, in terms of design, fabrication, and characterization. We observed both numerically and experimentally at around 100 GHz a narrow frequency band for which the metamaterial was low loss and had a negative index of refraction. We investigated flat and wedge shaped samples to support our characterization results. We analyzed the transmission band with respect to number of layers at the propagation direction and commented on the bulk nature of these metamaterials. Oblique response of the planar sample was also included in this study. Finally, we demonstrate a device, which yields a rather small angular width at the far field radiation pattern, and composed of a horn antenna and flat metamaterial slabs at the propagation direction. ©2009 IEEE.
  • Thumbnail Image
    ItemOpen Access
    Resonances in the electromagnetic scattering by very large finite-periodic grids of circular dielectric wires
    (IEEE, 2010-06) Natarov, D. M.; Benson, T. M.; Altıntaş, Ayhan; Sauleau, R.; Nosich, I.
    Diffraction of plane waves by infinite gratings is a classical research topic in the scattering theory. Using the Floquet theorem, one can reduce the infinite grating problem to the one-period problem. A characteristic feature of infinite-grating scattering is the drastic transformation of the scattering pattern and reflectance intensity if, in the process of changing the frequency or the angle of incidence, one of the Floquet harmonics is "passing over horizon." This phenomenon was first explained by Rayleigh [1] who studied theoretically the "anomalies" discovered experimentally by Wood [2]. In the simplest case of the normal incidence, these Rayleigh-Wood anomalies are observed if the period of the grating is multiple to the wavelength. © 2010 IEEE.