Link Budget Considerations for Reflecting Intelligent Surfaces in Radio Channels

Applying reflecting intelligent surfaces (RIS) in a communication channel paves the way to smart electromagnetic environments. The design modalities for reconfigurable meta-surfaces generating anomalous reflections are introduced. These meta-surface based RIS are evaluated for their usability in communication channels. A comparison is made with the state-of-the art technology: classical relaying stations. From this, the resulting requirements for the design of a RIS from a channel perspective are determined. An example set up in an realistic urban scenario as well as computational results are provided. It is shown that RIS, if properly designed, are a real alternative to relaying stations.