Modeling acoustic coherent communication under wind-driven ocean surface waves

Abstract

Wind raises time-varying roughness on air-sea interface, which deflects underlying sound and modifies underwater acoustic channel in short timescale. Performance degradations and system failures in underwater acoustic communication were reported due to wind-induced surface waves, especially for coherent communication systems which utilize phase information during the modulation. Here, we propose a controllable numerical approach for this problem: Realistic acoustic channels for different wind conditions are numerically simulated with wind-wave spectral methods and a 2-D rough-surface parabolic equation (PE) model; Then, these time-varying acoustic channels are tested with quadrature phase-shift keying (QPSK) modulation, one of the most fundamental modulation schemes for underwater acoustic coherent communication. Preliminary results suggest that in consideration of a time-varying environment, system performance for coherent communication degrades with increasing wind speed, as a result of increasing temporal variability of wind-impacted surface waves. Our numerical modeling method could be a helpful tool to study acoustic communication problems in time-varying ocean environments.