Performance Analysis of Mixed Underwater and Terrestrial OWC Systems Over Foggy Weather

Abstract

There has been extensive research on the performance of underwater optical wireless communication (UOWC) mixed with terrestrial OWC (TOWC) over atmospheric turbulence with pointing errors considering deterministic path loss under foggy weather conditions. Recent measurement campaigns provide a probabilistic behavior of the signal attenuation over the foggy channel. In this paper, we analyze the performance of a mixed TOWC-UWOC system by considering random foggy channels with pointing errors for the terrestrial link and lognormal distribution for underwater communication. We apply the decode-and-forward (DF) relaying to integrate the two technologies and analyze the performance of the proposed system by deriving analytical expressions of the outage probability, average SNR, and ergodic rate in terms of channel and system parameters. We use measurement data fitted parameters of the random fog and underwater channel to demonstrate the performance of mixed links under various foggy conditions and characteristics of underwater turbulence. We validate our derived mathematical expressions using numerical analysis and Monte Carlo simulations and demonstrate the performance of the relay-assisted mixed link over different foggy conditions and underwater turbulence.