Measurements of the nonlinear acoustic parameter of sea water via a device using reflected pulses

A method for measuring the nonlinear acoustic parameter of sea water and a device in the form of an immersed sonde are described. The method is based on the principle of registration of waves at the difference frequencies in water at consecutive reflections of high-frequency biharmonic acoustic pumping waves between the walls of a measuring cell. Some results obtained during vertical sounding of the upper layer of the sea to a depth of 100 m are presented.