Reconfigurable Intelligent Surfaces-Assisted I2V-Visible Light Communication

The performance of infrastructure-to-vehicle (I2V) visible light communication (VLC) systems with streetlight transmitters is heavily influenced by various infrastructure and transceiver parameters. Consequently, the connectivity between infrastructures and vehicles may experience system outages, particularly as the vehicles move farther away from the streetlight poles. To address these challenges, this paper introduces an innovative solution based on the deployment of optical reconfigurable intelligent surfaces (O-RIS) technology. The proposed approach utilizes a non-sequential ray tracing technique to model the I2V-VLC system and its channel. It calculates both the direct channel gains and the channel gains obtained through the use of O-RIS for different combinations of transceiver, RIS, and infrastructure settings. The paper further analyzes the system bit error rate (BER) and data rate and derives closed-form expressions to determine the required number of RIS elements needed to achieve targeted BER and data rate. Utilizing that, the paper investigates the impact of various factors on the system's performance. The results emphasize that receiver diameter, interspacing between the poles, and the transmit power budget significantly influence the total number of required RIS elements.