The Rumble in the Millimeter Wave Jungle: Obstructions Vs RIS

Abstract

Reconfigurable intelligent surfaces (RISs) have emerged as a key technology for future communication systems. RISs are arrays of tunable reflecting elements that provide controllable propagation channels by smartly shaping incident electromagnetic (EM) waves. Analysis and improvement of RIS-aided systems require the definition of accurate path loss models that consider environmental effects often encountered in practical applications. In this paper, we derive a path loss model for RIS-assisted communications to account for the attenuation induced by the transmission medium and randomly located obstructions. More precisely, this study focuses on assessing the impact caused by Poisson-located obstructing objects on RIS-assisted millimeter wave links. To this end, we evaluate the outage probability yielded by RIS-aided systems in indoor environments with antenna beam-steering and random obstructions. We obtain extensive simulation results to assess the impact of RIS considering different parameters, such as the minimum signal-to-noise ratio (SNR) necessary for successful reception, the operating frequency, the density of the Poisson process used for object placement, and the object size.