Comparing Speckle Imaging Methods

Abstract

We will compare speckle imaging reconstruction results for several speckle imaging approaches. In particular, we will compare and contrast four methods: 1) Knox-Thompson, using a hidden phase-finder in the object spectrum phase reconstruction; 2) Knox-Thompson, using a phasor-based phase reconstruction; 3) Bispectrum, using only two bispectrum planes; Bispectrum, using four bispectrum planes. In each application of the four approaches we first calculate the modulus of the object spectrum using a Wiener-Helstrom filter to remove the speckle transfer function. The methods then differ only in their object spectrum phase reconstructions. In the simulations, we will assume that the only aberrations are those introduced by atmospheric turbulence, setting the ratio of the telescope diameter, D, to the Fried Parameter equal to ten. Additionally, we assume that the focal-plane detector array is photon-noise limited, the illumination is narrow-band (essentially monochromatic) and the atmosphere is static during each data frame. First, we will implement all four methods on a simple binary star object at low photon-per-frame light levels. Next, we will apply the methods to complex extended objects.

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Document Details

Document Type
Technical Report
Publication Date
Sep 01, 2009
Accession Number
ADA531801

Entities

People

  • Andrew P. Ongstad
  • Gregory C. Dente
  • Michael L. Tilton

Organizations

  • Air Force Research Laboratory

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Atmospheric Motion
  • Binary Stars
  • Detectors
  • Diameters
  • Difference Equations
  • Diffraction
  • Equations
  • Simulations
  • Spearography
  • Spectra
  • Stars
  • Telescopes
  • Transfer Functions
  • Turbulence
  • Two Dimensional

Fields of Study

  • Physics

Readers

  • Image Processing and Computer Vision.

Technology Areas

  • Space
  • Space - Space Objects