Accession Number:

ADA014111

Title:

Characterization of Active Underwater Acoustic Channels. Part I. A New Formulation for Scattering by Random Media and Interfaces,

Descriptive Note:

Corporate Author:

TEXAS UNIV AT AUSTIN APPLIED RESEARCH LABS

Personal Author(s):

Report Date:

1974-12-01

Pagination or Media Count:

109.0

Abstract:

A general approach to scattering phenomena is developed and applied specifically to underwater acoustic scattering situations involving the medium and its interfaces. The fundamental elements of the method are the development of the available scattering elements into a hierarchy of independent scatter processes, based on the scatterers activated, at any given instant. This, with the governing class of Langevin equation e.g., forms of the scalar wave equation here permits a corresponding development, in linear superposition, of the received, scattered field x sub m as a hierarchy of independent processes, x sub mk, k0,1,2.., representing different scales of inhomogeneity which may be present in the medium, or upon its interfaces. First- and second-order moments covariances and generalized spectra are obtained in canonical form, representing global properties of the channel and the local properties of the medium itself. A number of probability densities are also obtained in important limiting cases, e.g. various conditional normal p.d.f.s. Part I concludes with some remarks on an experimental program, designed to test and quantify various aspects of the general model, both for studies of the medium itself and its associated interfaces, and for the broad class of statistical communication applications, such as detection, extraction, classification, communications per se, as well as signal and aperture design problems.

Subject Categories:

  • Acoustic Detection and Detectors
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE