Accession Number:

ADA612085

Title:

Stochastic Models and Robust Estimation for Broadband Acoustic Mode Signals

Descriptive Note:

Annual rept.

Corporate Author:

GEORGE MASON UNIV FAIRFAX VA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING

Personal Author(s):

Report Date:

2006-09-30

Pagination or Media Count:

12.0

Abstract:

The long term goals of this project are to develop stochastic models for broadband mode signals propagating in fluctuating ocean environments and to design robust signal processing techniques for these ocean environments. To develop a greater understanding of broadband mode signals in fluctuating ocean environments, this project focused on several closely-related research objectives. The first objective was to characterize mode fluctuations at megameter ranges using experimental measurements and simulations. Mode arrivals at long range are very complicated due to internal-wave-induced coupling. From a theoretical standpoint, the effects of internal waves on long-range sound propagation are not thoroughly understood, and much of the previous work in this area focused on the ray arrivals because they are amenable to analysis via the geometrical optics approximation. Characterizing the fluctuations is the first step towards the long-term goal of developing a sufficiently general model of mode propagation that explains recent experimental observations and clarifies the relationship between mode and ray representations of the field. The second objective of this project was to develop a framework for mode processing that mitigates the effects of environmental mismatch, sensor failures, and interference. Since mismatch is a problem that plagues many sonar applications, this work has implications beyond the current project.

Subject Categories:

  • Statistics and Probability
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE