Composite vortex manipulation as a design tool for reflective intelligent surfaces

To achieve a smart electromagnetic (EM) environment, several implementation challenges need to be addressed. Among them, the practical realization of low-cost and easily deployable reconfigurable intelligent surfaces (RISs) is a crucial objective for both the applied EM and wireless communication communities. In this framework, we propose a new design strategy for adding reconfigurability to reflective metasurfaces (MTSs) and, thus, implementing RISs. In particular, we exploit the insights of CV theory to control the overall scattering pattern of reflective MTSs and reduce the complexity of the control system. Indeed, instead of continuously tuning the response of each MTS element, the proposed solution requires only switching on and off the response of a portion of the MTS itself, allowing for an easier practical implementation. The results of an analytical analysis and a set of numerical full-wave simulations confirm the effectiveness of the proposed approach.