  Rapid advances in metamaterial technology are enabling the engineering of
wave-matter interactions heretofore not realized and functionalities with
potentially far-reaching implications for major challenges in the fields of
energy conservation and radio frequency (RF) communication. We propose a
visibly and RF transparent composite metasurface utilizing dielectric-metal
spectrally selective coatings with high NIR control and low thermal emissivity,
thus achieving a multi-functional metasurface capable of enhancing 5G
communication efficiency and exhibiting energy conservation features. The
proposed meta-glass yields 92% peak RF transmission at 30 GHz which corresponds
to 20% and 90% enhancement when compared to plain glass and low-emissive glass
substrates. This meta-glass possesses 86% peak optical transparency at
$\lambda=550 nm$, $>$60% near-IR reflection, and $>$ 80% mid-IR reflection
which corresponds to $\approx$ 0.2 thermal emissivity. The proposed metasurface
design is highly flexible and can be tuned to operate over different frequency
ranges owing to its frequency scalability. This study provides a better
alternative using earth-abundant materials compared to low-emissive glass based
on indium tin oxide (ITO) while boosting the efficiency of 5G communication
amenable to window systems demanding simultaneous functionalities for emergent
smart/energy-efficient buildings/cities and autonomous transportation
applications.
