Ricerc@Sapienza

An improved low-profile printed antipodal drop-shaped dipole antenna for wide-band wireless applications is presented. The proposed radiating structure is integrated with a planar metal reflector useful to enhance antenna gain up to 5.5 dBi and the frontto- back ratio up to 21 dB.The geometry of reflector, feeding line, and dipole arms is optimized in order to achieve a broad operating bandwidth useful to meet the requirements of modern wireless communication protocols.

A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account.

The complex mode spectra of a grounded anisotropic dielectric slab (GADS) excited by a horizontal magnetic dipole are presented in the low THz range. A liquid crystal mixture with high birefringence, low dispersive behavior and moderate losses at THz frequencies is selected as anisotropic layer. The dispersion curves of the complex modes (in both the surface-wave and leaky-wave regime) supported by the GADS are compared to those supported by the equivalent isotropic grounded dielectric slab GDS with the ordinary and the extraordinary components of the liquid crystal permittivity tensor.