To solve the problems of measuring wave parameters on the water surface, it is proposed to use an underwater acoustic wave gauge. Underwater observation of surface waves has several advantages over sea buoys and string wave gauge. Underwater instruments can operate anywhere in the World Ocean and do not require mounting on the rigid structure of offshore platforms. Underwater methods are not sensitive to any atmospheric conditions, for example, they can work in hurricane winds and even in freezing waters. There are various devices for underwater measurement of wave parameters. However, they are united by the desire to determine the wave spectrum, which requires making the antenna beam as narrow as possible, and the measurement results will depend on the installation depth. Because of this, it is necessary to limit the region of the measured spectrum only to low-frequency (long) waves, usually the upper limit is about 0.35 Hz. In this work, experimental testing of a new approach for determining the integral parameters of waves by the shape of the reflected acoustic pulse averaged over space and time, is carried out. A feature of this approach is the insensitivity to the instrument installation depth (deeper installation will even provide shorter time averaging). Another important advantage of this approach is the ability to measure the same surface parameters that affect the characteristics of microwave backscattering with the same wavelength.