Path Loss Modeling for the RIS-Assisted Channel in a Corridor Scenario in mmWave Bands.

Reconfigurable intelligent surface (RIS) has been envisioned as a promising technology for the sixth generation (6G) wireless mobile communication systems because of its ability to change the channel actively and low power consumption. The study of path loss modeling is an important part of RIS-assisted channel research. This paper analyzes the path loss of the RIS-assisted wideband channel based on the field channel measurements at 26 GHz in an indoor corridor scenario. First, we introduce three path loss models considering RIS-assisted channel features and compare their performance via the root mean square error (RMSE) and the path loss exponent. This study verifies that a variant of the multiplicative-distance model is more suitable for RIS-assisted channel path loss modeling. Secondly, by using this model, we carry out path loss modeling in the corridor scenario. The corridor scenario is a typical waveguide-like structure, hence we consider the waveguide effect in the path loss modeling and propose a dual slope path loss model suitable for the RIS-assisted channel in a waveguide-like structure scenario.