Experimental evaluation of Luneburg lens using radial holes for relative permittivity distribution

In this paper, we describe a novel 3-D Luneburg lens using radial holes. A can suppress the side lobe of antenna and increase gain. The prototype was fabricated 30mm radius dielectric sphere with uniform permittivity by 2.1 many holes 1mm radius, called drilled vertically on surface. relative distribution is realized changing number depth five types To confirm effectiveness lens, far-field radiation pattern at 25GHz measured flanged rectangular waveguide as wave source. It achieved high gain 22.4dBi. generally agreed well theoretical validity quasi-millimeter confirmed. be used for beam steering in 5G/6G base stations.