Phase Space Representation of Sound Fields in Lake Kinneret

This article presents the analysis of pulsed sound fields recorded by a vertical array in Lake Kinneret (Israel). The transition from the traditional representation of the complex amplitude of the received field as a function of depth and time to a function representing the field distribution in the phase space 'depth-angle-time' is considered. Due to the absence of multipath and problems with caustics, the sound field distribution in phase space is less sensitive to environmental disturbances and therefore more predictable than in configuration space. The transition is carried out using the coherent state expansion developed in the quantum theory. This approach, intended for the use in ocean acoustics, is tested in a well-controlled lake environment. The measured distribution of the field intensity in the phase space agrees with the calculation performed with an idealized environmental model. It is shown that this distribution can be taken as the input for solving the problem of source localization. The results of data processing demonstrate the possibility of using the coherent state expansion for isolating the field component formed by a given beam of rays.