  An innovative approach for the synthesis of inexpensive holographic smart
electromagnetic (EM) skins with advanced beamforming features is proposed. The
complex multiscale smart skin design is formulated within the Generalized Sheet
Transition Condition (GSTC) framework as a combination of a mask-constrained
isophoric inverse source problem and a micro-scale susceptibility dyadic
optimization. The solution strategy integrates a local search procedure based
on the iterative projection technique (IPT) and a System-by-Design (SbD)-based
optimization loop for the identification of optimal metasurface descriptors
matching the desired surface currents. The performance and the efficiency of
the proposed approach are assessed in a set of representative test cases
concerned with different smart skin apertures and target pattern masks.
