Evaluating the Impact of Sea State Variation on Multi-Frequency Electromagnetic Propagation in the Marine Atmospheric Boundary Layer

Electromagnetic (EM) signal propagation in the marine atmospheric boundary layer (MABL) is influenced by both atmospheric and oceanic variables, including humidity gradients and ocean surface waves. Ocean surface waves may affect propagation via incoherent interference and enhance multipath scattering, in turn, generally increasing signal loss. As such, it is important to understand and quantify the impact of ocean surface waves on propagation of various EM frequencies typically utilized in the marine environment. EM propagation was modeled for wind-driven and mixed (i.e., wind and swell) sea states, using varying wind speeds, under a variety of evaporation ducting conditions, and three frequencies. Wave steepness for each sea state was evaluated against propagation loss, revealing a cohesive negative relationship across all frequencies, trapping scenarios, and sea states.