Compact, Low-Dispersion, Metalo-Dielectric Gradient - Index Lenses with Additive Manufacturing

This paper presents a metalo-dielectric gradient-index (GRIN) lens which combines metamaterial and dielectric unit cells to realize a wide refractive index range for compact lens design. The selected unit cell library is designed to have low-dispersion characteristics across the K frequency band. The lens is simulated in a parallel-plate waveguide and achieves an absolute gain of 22.5 dB at 28 GHz while maintaining an aperture efficiency greater than 60% with an average greater than 70%. This lens design takes advantage of a low-cost additive manufacturing technique for rapid realization of lens antennas.