Design of Single Layer Optically Transparent Reflectarray for 5G Outdoor and Indoor Coverage Enhancement

A new type of optically transparent metasurface which can be integrated into window glass for 5G outdoor and indoor coverage enhancement is proposed in this paper. The sub-wavelength element achieved peak return loss within 2.8dB and phase variation more than 360° during 26GHz - 30GHz. For verification, a simulation demonstration of 25 × 25 element reflectarray with the focus to diameter ratio (F/D) of 0.8 showed that the gain at the center operating frequency 28GHz could reach 24.5dBi, with a higher radiation efficiency over 76.8%.