Exploiting Reconfigurable Intelligent Surfaces to Achieve Multi-Receiver Physical Layer Security

Secure and private communications can be made possible by operating at different levels of the communication stack. One possibility is to work directly at the physical layer, with physical layer security (PLS) techniques. In this work, we propose a PLS-based approach towards secure and private communications, in particular by exploiting reconfigurable intelligent surfaces (RISs). By properly tuning the configuration of the RISs it is possible to enable communication with a set of intended receivers while making the signal unintelligible in nearby areas. This work shows the effectiveness of the approach, while also highlighting its limitations and the challenges that need to be tackled for realizing it in practice.