A fully planar antenna for millimeter-wave and 5G communications based on a new CSRR-enhanced substrate-integrated waveguide

We present a fully planar, easy to fabricate antenna for millimeter-wave communications, based on a new substrate-integrated waveguide (SIW). The SIW itself is entirely planar, since it is designed using series of side-by-side complementary split-ring resonators (CSRR), instead of vias, with the CSRR being etched on top and bottom metal ground surfaces that cover the dielectric substrate. This metamaterial-inspired structure provides a single-negative effective material parameter behavior that blocks wave propagation to the perpendicular direction. Hence, two parallel structures of this kind can be used to design an SIW, with propagation losses comparable to the conventional one. The antenna structure is consequently designed, by the use of proper cavities within the substrate and radiating slots on the ground structure and provides an easy to fabricate alternative for millimeter-wave and 5G communications.