Scattering from Rock and Rock Outcrops

Abstract

In terms of target detection and classification, scattering from exposed rock on the seafloor, (i.e., individual rocks and rock outcrops) presents some of the most difficult challenges for modern MCM and ASW sonar systems in shallow water. Work on characterizing, modeling and simulating mean levels and other statistical measures of acoustic scattering from rocks and rock outcrops is therefore critical. Unfortunately (and curiously) information on scattering from underwater rock and outcrops is almost non-existent. Scattering from rock outcrops is not simple enough to be encompassed by a single scattering strength curve, but has a variety of expressions depending on the exact geomorphology of the rock. Smoothed surfaces may actually scatter less than surrounding sediment; curvature may dramatically affect scattering and rough areas as seen in the plucked area on the rock outcrop in Fig. 1, display high variability which could pose difficulty for target detection and classification systems. The primary long-term goal of this research project is to increase our understanding and modeling of high-frequency acoustic scattering from rock and rock outcrops. In addition to an increase in our basic understanding of the characteristics of scattering from rock, any resulting advances in modeling would be useful for improving simulation capabilities and for improving detection and classification tools. Inverse models based on forward models would be essential for using sonar systems for remote sensing of seafloor properties. An understanding of spatial coherence functions for isotropic and anisotropic rough seafloor surfaces could allow a method for separating natural target -like objects such as rough rock from man-made targets.

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Document Details

Document Type
Technical Report
Publication Date
Sep 30, 2013
Accession Number
ADA598692

Entities

People

  • Anthony P. Lyons

Organizations

  • Pennsylvania State University

Tags

Communities of Interest

  • Autonomy

DTIC Thesaurus Topics

  • Acoustic Scattering
  • Acoustics
  • Autonomous Underwater Vehicles
  • Detection
  • False Alarms
  • Frequency
  • Grazing Angles
  • High Resolution
  • Measurement
  • Models
  • Physical Properties
  • Pressure Distribution
  • Remote Sensing
  • Scattering
  • Simulations
  • Synthetic Aperture Sonar
  • Target Detection

Readers

  • Acoustical Oceanography.
  • Seismology

Technology Areas

  • Autonomy