An experimental model of surface reflection in the underwater anechoic basin at KRISO

The behavior of propagating waves in the ocean is highly dependent on the surface geometry of the ocean as well as the spatial distributions of temperature, pressure, and salinity in the media. Waves are refracted due to the spatial variation of the media properties, reflected by free surfaces and bottoms, and scattered by small floating particles. These phenomena make it difficult to identify original signals during acoustic measurements. Among them reflection has the most significant effect on signal distortion by building up multi-paths between transmitters and receivers. In this research, a surface reflection model is investigated by an experimental approach. The experiments were performed in the underwater anechoic basin at KRISO/KORDI. It is found that a reflected wave is composed of three parts: negative and positive peaks and a ringing component. Among them the negative peak plays a dominant role in the surface reflection.