Restoring in-phase emissions from non-planar radiating elements using a transformation optics based lens

The broadband directive in-phase emission from an array of sources conformed cylindrically is numerically and experimentally reported. Such manipulation is achieved through the use of a lens designed by transformation optics concept. The all-dielectric lens prototype is realized through three-dimensional (3D) polyjet printing and presents a graded refractive index. A microstrip antenna array fabricated using standard lithography techniques and conformed on a cylindrical surface is used as TE-polarized wave launcher for the lens. To experimentally demonstrate the broadband focusing properties and in-phase directive emissions, both the far-field radiation patterns and the near-field distributions have been measured. Experimental measurements agreeing qualitatively with numerical simulations validate the proposed lens and open the way to inexpensive all-dielectric microwave lenses for beam forming and collimation. (C) 2015 AIP Publishing LLC.