Modulation Transfer Function Analysis of Kelvin Wakes and Ambient Wave Images

Abstract

Synthetic aperture radar (SAR) images collected during a 1989 surface ship wake experiment are analyzed using a linear imaging model which includes contributions due to velocity bunching, tilt modulation and hydrodynamic modulation as well as azimuth falloff and coherent speckle effects. This model adequately predicts the overall shape of the image spectrum for ambient waves as observed from three different look directions, although there are some discrepancies for range-traveling waves which are attributed to uncertainties in the tilt and hydrodynamic modulation. Inversion of the model to yield estimates of the Kelvin wake and ambient wave heights appears to be successful, although the results are sensitive to the value assumed for the surface decorrelation time.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1991
Accession Number
ADA244995

Entities

People

  • David R. Lyzenga
  • John A. Burns
  • N. Malinas

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms

DTIC Thesaurus Topics

  • Algorithms
  • Amplitude
  • Data Analysis
  • Data Sets
  • Frequency
  • Inertial Navigation
  • Inertial Navigation Systems
  • Intensity
  • L Band
  • Ocean Waves
  • Power Spectra
  • Radar
  • Radial Velocity
  • Synthetic Aperture Radar
  • Transfer Functions
  • Two Dimensional
  • Waves

Fields of Study

  • Physics

Readers

  • Acoustical Oceanography.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Radar Systems Engineering.