Ergodic Capacity Optimization for RSMA-Based UOWC Systems Over EGG Turbulence Channel

Underwater optical wireless communication (UOWC) systems encounter significant challenges from oceanic turbulence and pointing errors. This study investigates the performance of rate-splitting multiple access (RSMA)-enabled multi-user UOWC systems operating over an exponential-generalized gamma-distributed oceanic turbulence channel with pointing errors. An accurate analytical expression for the sum ergodic capacity is derived, and a particle swarm optimization-based alternative-search algorithm is developed to jointly optimize both transmit power allocation and the position of the source node for maximizing the sum ergodic capacity. The effectiveness of the proposed algorithm in maximizing system capacity over several benchmark schemes is verified via extensive simulations.