Performance Analysis of ORIS-Assisted UOWC System over Turbulence with Pointing Errors

This paper investigates performance of an optical reconfigurable intelligent surface (ORIS)-assisted underwater optical wireless communication (UOWC) system under Gamma-Gamma oceanic turbulence and pointing errors. Exact closed-form expressions for outage probability and ergodic capacity are derived and validated through extensive Monte Carlo simulations with 10⁷ channel realizations. Subsequently, the ORIS-assisted system and a conventional decode-and-forward (DF) relay-assisted UOWC system are compared across different turbulence levels, pointing error severities, and numbers of reflecting elements. The results reveal that the ORIS-assisted system consistently outperforms the DF relay approach, offering notable improvements in both outage probability and ergodic capacity, particularly under harsh oceanic conditions. The outage results are also consistent with asymptotic predictions at high signal-to-noise ratio (SNR), and ORIS effectively enhances ergodic capacity by mitigating impairments passively without introducing additional noise. The close agreement between analytical and simulation results confirms the accuracy of the developed models and the predicted diversity order.