Imaging theory and mitigation in extreme turbulence-induced anisoplanatism

Abstract

Interestingly, Speckle Imaging (SI) is highly effective at recovering images of extended scenescorrupted by turbulence-induced, anisoplanatic distortion. Current imaging theory cannot explainthe efficacy of SI techniques. However, the operational implications of understanding andexploiting these empirical observations would be enormous, for example, vastly improving theresolution of airborne slant-path long range imaging systems. The objective of the proposedresearch is to improve our understanding of imaging under conditions where the isoplanaticangle is on the order of, or smaller, than the sample rate of the imaging system. I refer to theseconditions as being extremely anisoplanatic. The proposed research contributes to this objectivethrough three lines of inquiry. First, I propose to investigate if the piston removed anisoplanaticerror saturates as the ratio of the aperture size to the atmospheric coherence radius approachesunity. Saturation of anisoplanatic errors may explain the efficacy of Speckle Imaging (SI)techniques over wide fields of view and provide new guidance on the design of standoff imagingand beam control systems used in scenarios involving extreme anisoplanatism. Next, I willinvestigate the idea that a multitude of contributions from extended scenes combine such thattheir effect can be modeled as a zero-mean Gaussian random process under the central limittheorem. The consequence being a reduction in the signal to noise ratio of SI quantitates whilestill allowing for scene recovery. Finally, I will explore the use of novel plenoptic imaginggeometries for simultaneous wave front sensing and scene recovery in extreme anisoplanatism.The optimal design of such as system may also lead to beam control systems capable ofcorrecting turbulence-induced phase errors in real-time.

Document Details

Document Type
DoD Grant Award
Publication Date
May 02, 2017
Source ID
FA95501710201

Entities

People

  • Jeremy P. Bos

Organizations

  • Air Force Office of Scientific Research
  • Michigan Technological University
  • United States Air Force

Tags

Fields of Study

  • Physics

Readers

  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Data Mining and Knowledge Discovery.
  • Image Processing and Computer Vision.