Accession Number:

ADA633834

Title:

High Resolution Focusing Analysis and Inversion for Small Scatterer Detection

Descriptive Note:

Corporate Author:

COLORADO SCHOOL OF MINES GOLDEN CENTER FOR WAVE PHENOMENA

Personal Author(s):

Report Date:

1999-09-30

Pagination or Media Count:

6.0

Abstract:

LONG-TERM GOAL. The long-term goal of this project is to develop software to invert acoustic data from a towed sourcereceiver array for simultaneous velocity analysis, detection and material characterization of small-scale 7 to 15 cm scatterers in the shallow ocean and seabed sediments. Detection will be achieved by providing a reflector map of the target region. Material characterization is provided through estimates of angularly dependent reflection coefficients at the surface of the target over multiple angles angle versus offset analysis provides a basis for characterizing the internal material parameters of the target. OBJECTIVES. The immediate objective is to complete the development of a computer code for towed array data that back propagates the data with a wavespeed that varies in all three spatial variables. This software is also to be integrated with software to carry out velocity analysis so that the change in wavespeed from the water column to the seabed can be properly treated. The more long-term objectives are to continue to incorporate developments in the underlying theory into the software being developed for this application. For example, the theory is currently being extended to multi-pathing---the case in which the ray trajectories from a point scatterer at depth form caustics in the subsurface, leading to multiple arrivals at the same observation point on the receiver array.

Subject Categories:

  • Physical and Dynamic Oceanography
  • Miscellaneous Detection and Detectors
  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE