3D printed dielectric lens for the gain enhancement of a broadband antenna
Muhammad S. Anwar, Hasan Abufanas, Axel Bangert
Abstract
A novel 3D printed dielectric lens to enhance antenna gain parameters is presented. The lens is fabricated using a fused deposition method (FDM) which is a cost-effective and an efficient 3D printing technique. Poly-methyl methacrylate (PMMA) is used as a dielectric material due to its good RF properties. The thickness of the dielectric lens is 14 mm and provides a gain enhancement of up to 6.9 dBi over a wide frequency range. The dielectric lens is designed and computationally analyzed to demonstrate refractive index value close to zero. It has been shown that impedance-matched near-zero refractive index lens geometry eliminates strong reflections, and consequently enhances the antenna gain. A correlation is established between the individually, stacked unit cell layers and near-zero refractive index cut-off frequencies. The claim is substantiated through measured results using a broadband Vivaldi antenna. A gain enhancement of up to 6.9 dBi is recorded for the bandwidth from 13.5 to 24 GHz. An excellent correlation is reported between the measured and simulated results.