Outdoor Synthetic Aperture Acoustic Ground Target Measurements

Abstract

A novel outdoor synthetic aperture acoustic (SAA) system consists of a microphone and loudspeaker traveling along a 6.3-meter rail system. This is an extension from a prior indoor laboratory measurement system in which selected targets were insonified while suspended in air. Here, the loudspeaker and microphone are aimed perpendicular to their direction of travel along the rail. The area next to the rail is insonified and the microphone records the reflected acoustic signal, while the travel of the transceiver along the rail creates a synthetic aperture allowing imaging of the scene. Ground surfaces consisted of weathered asphalt and short grass. Several surface-laid objects were arranged on the ground for SAA imaging. These included rocks, concrete masonry blocks, grout covered foam blocks; foliage obscured objects and several spherical canonical targets such as a bowling ball, and plastic and metal spheres. The measured data are processed and ground targets are further analyzed for characteristics and features amenable for discrimination. This paper includes a description of the measurement system, target descriptions, synthetic aperture processing approach and preliminary findings with respect to ground surface and target characteristics.

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Document Details

Document Type
Technical Report
Publication Date
Apr 19, 2010
Accession Number
ADA518719

Entities

People

  • Erik Rosen
  • Jay Marble
  • Joe Vignola
  • John Judge
  • Mehrdad Sournekh
  • Pete Gugino
  • Steven Bishop
  • Therese-ann Ngaya

Organizations

  • The Catholic University of America

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Acoustics
  • Aspect Angle
  • Concrete
  • Detection
  • Detectors
  • Frequency
  • Image Processing
  • Image Reconstruction
  • Images
  • Loudspeakers
  • Materials
  • Measurement
  • Microphones
  • Signal Processing
  • Synthetic Aperture Radar
  • Transceivers
  • Wave Propagation

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Acoustics.
  • Radar Systems Engineering.