Poster: Multi-Receiver Physical Layer Security Using Reconfigurable Intelligent Surfaces

Physical layer security (PLS) aims at introducing security and privacy mechanisms directly at the signal level, as an additional measure on top of what is provided by higher layers. One recent approach proposes to exploit reconfigurable intelligent surfaces (RISs) to enhance signal quality towards an intended receiver while generating disrupting interference towards a potential eavesdropper. Existing approaches consider single receiver/single RIS scenarios in a simplified setting, making it difficult to evaluate the actual applicability of the approach. In this work we extend the existing model to work with multiple receivers and multiple RISs discussing secrecy characteristics in the spatial domain, rather than for a single eavesdropper. Our results show the applicability of our extended approach together with the limitations of using passive RISs compared to active ones, as well as highlighting the challenges related to mobility.