Abstract:

The acoustic reflection coefficient of the ice layer is calculated, and the characteristics of acoustic propagation loss in the surface layer are analyzed. The ice layer is approximated as a flat cover, and a physical model of ice reflection is established. The reflection coefficient of ice layer is calculated based on the physical acoustic parameters of ice. The sound field propagation loss under the ice cover is obtained using the Bellhop ocean acoustic propagation model, and the relationship between the propagation loss and the acoustic frequency or the sound source depth is analyzed. The reason for the frequency selectivity of the ice channel can be explained based on the calculation results of the reflection coefficient of the ice layer. The results show that the propagation of sound field under the ice cover has obvious frequency selectivity, which is determined by sound wave frequency and the thickness of the ice layer.

Key words: ice sheet, reflection coefficient, transmission loss, underwater acoustic channel