Shaping the Scattering Pattern of a Reconfigurable Intelligent Surface Through the Manipulation of Composite Vortices

In this contribution, we provide new insights into the possibility offered by the composite vortex theory to manipulate the scattering pattern of Reconfigurable Intelligent Surfaces (RISs). In particular, by dividing the RIS into two concentric circular regions imparting a different helical profile to the incident field, the ability to control the number and position of the phase singularity points of the overall composite vortex is exploited to customize the response of the RIS and achieve peculiar shapes of the scattering pattern (e.g. a saddle- or a sectorshaped pattern).