Ergodic Capacity of a Vertical Underwater Wireless Optical Communication Link Subject to Misalignment

Typical underwater communication scenarios in-clude data transfer between a surface platform and an under-water unit. We investigate the interest of underwater wireless optical communications (UWOC) for such scenarios, where the link performance is affected by transmitter-receiver misalignment in practice. The focus is on the channel ergodic capacity based on an elaborate statistical model of the aquatic channel accounting for different phenomena such as surface wind speed, beam directivity, underwater unit beam misalignment, and solar noise, as well as the transmitter/receiver parameters. The presented results demonstrate the channel effects and provide interesting insight into the design of such links.