Coat Measurements and Analysis

Abstract

Several propagation problems have been investigated using multidither Coherent Optical Adaptive Techniques (COAT). Multidither tracking and focus controls have been implemented into a computer simulation and into the DARPA/ RADC experimental COAT model which previously had only 18 channels of planar phase control. Compensation for turbulence has been demonstrated both analytically and experimentally using these new controls. COAT-system/target- signature interaction effects have been studied experimentally and analytically. The experimental results indicate that the deleterious effects of target-induced speckle modulations are not as serious as suggested by earlier work. Computer simulation studies tend to support this observation, but are limited by inadequate knowledge of the amplitude and frequency spectrum of speckle modulations produced by realistic targets. Experimental thermal blooming studies in scaled laboratory experiments have shown a 35% improvement in peak target irradiance. Computer simulation studies of thermal blooming indicate that a return-wave COAT system may reduce the target irradiance under strong blooming, but this cannot occur with an irradiance maximization technique such as outgoing-wave multidither COAT.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 1975
Accession Number
ADB008416

Entities

People

  • Chia-Yi Yeh
  • J. E. Pearson
  • M. E. Pedinoff
  • S. A. Kokorowski
  • W. P. Brown

Organizations

  • HRL Laboratories

Tags

Communities of Interest

  • C4I
  • Energy and Power Technologies
  • Weapons Technologies

DTIC Thesaurus Topics

  • Acousto-Optic Modulators
  • Adaptive Optics
  • Amplitude Modulation
  • Atmospheric Motion
  • Automatic Gain Control
  • Computer Simulations
  • Diffraction
  • Distortion
  • Lasers
  • Measurement
  • Modulation
  • Modulators
  • Power Spectra
  • Statistical Analysis
  • Target Signatures
  • Test And Evaluation
  • Thermal Blooming

Fields of Study

  • Physics

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Optical Physics and Photonics.
  • Radar Systems Engineering.