Short-term fading model for signals reflected by ocean surfaces in underwater acoustic communication

A short-term fading model based on rough surface theory is proposed to estimate stochastic characteristics of signals reflected by time-varying ocean surfaces in underwater acoustic channels. With this method, probability density functions of the fluctuations in the propagation delay and magnitude, and the Doppler spectral densities are provided with respect to wind speeds. After conducting several experiments and verifying them by comparing with the measurements, it is shown that the model accurately estimates the stochastic characteristics. The proposed model is valid when the transmitter and receiver locate sufficiently far away from the ocean surface.