Dual-Band Electromagnetic Skin With Independent Reflection Performance at 28 GHz and 39 GHz for 5G Millimeter-Wave Communications

This letter presents a dual-band smart electromagnetic skin (SES) for millimeter-wave 5G applications, which provides simultaneous operation at the (28, 39) GHz bands with independent reflection performance at each band (i.e., different incidence and reflection angles). The SES consists of a two-layer reflectarray panel of 202.5 mm side, which produces two independent reflected beams in dual-polarization when it is illuminated from two different feeders (one for each operating band). A prototype of the SES has been fabricated and tested, and the measured radiation patterns agree well with the simulations. The 2 dB gain bandwidth exceeds 14.3% at 28 GHz (26 GHz to 30 GHz) and 5% at 39 GHz (38 GHz to 40 GHz). The dual-band SES will contribute to enhancing 5G communications by producing two independent reflected beams when it is illuminated from two faraway base stations, each operating at a different frequency.