Outage Performance of IRS-Assisted Underwater Optical Wireless Communication Systems over Combined Channel Model

This paper investigates the performance of an intelligent reflecting surface (IRS)-assisted underwater optical wireless communication (UOWC) system in considering oceanic propagation loss, oceanic turbulence, and pointing errors. Pointing errors induced by IRS vibration is the main factor that causes the performance degradation of IRS-assisted UOWC systems. Unlike previous works that employed zero boresight pointing error model for the performance analysis of UOWC systems, in this study, we develop a nonzero boresight pointing error model. In addition, we derive the approximation formula for the comprehensive channel model that combines three separate models including the propagation loss model, log-normal oceanic turbulence model, and the nonzero boresight pointing error model. The outcomes of this study reveal that the vibration of an IRS-installed buoy/ship severely impacts the system outage performance. Insightful discussions based on the numerical results are useful for the practical system design of the IRS-assisted UOWC system.