Reducing complexity of intelligent surfaces by controlling the beam-width of the illuminating field

In the development of smart electromagnetic environments, Reconfigurable Intelligent Surfaces (RIS) emerge as pivotal elements. However, some challenges persist toward their deployment in a real-world scenario, mainly due to the complexity and costs associated with reconfiguring a large RIS with good efficiency. In this context, this contribution explores a novel solution to simplify the inherent complexity of RIS. By exploiting the characteristics of composite vortices and shifting reconfigurability to the illuminating field, we propose a method to deploy static surfaces whose characteristics are properly engineered for reflecting a vortex mode. This paradigm allows for the manipulation of scattering patterns through the control of the beam-width of the impinging field.