COAT Measurements and Analysis

Abstract

Compensation for thermal blooming distortions has been studied using multidither coherent optical adaptive techniques (COAT) in scaled laboratory experiments. An 18 element, visible wavelength, COAT systems was able to effect only a small improvement in peak target irradiance for forced-convection blooming. Similar results were observed with a truncated Gaussian beam using a computer simulation which models atmospheric thermal blooming and uses a phase conjugate COAT control algorithm to adjust the transmitted beam phase. Refinements in the experimental apparatus to eliminate buoyancy effects are discussed and a design is presented for incorporating adaptive pointing and focus controls into the COAT system. Two designs for an artificial turbulence generator are presented along with a design for adding adaptive tracking and focus controls to the RADC/COAT system. Preliminary COAT studies without turbulence or blooming but with complex moving targets are reported. Normal COAT system operation is observed with all targets if the receiver has sufficient resolution and if the system signal-to-noise ratio is large enough for stable operation.

Open PDF

Document Details

Document Type
Technical Report
Publication Date
May 01, 1975
Accession Number
ADA011707

Entities

People

  • James E. Pearson

Organizations

  • HRL Laboratories

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Adaptive Optics
  • Atmospheric Motion
  • Automatic Gain Control
  • Buoyancy
  • Computer Simulations
  • Control Systems
  • Convection
  • Distortion
  • Fluid Dynamics
  • Intensity
  • Measurement
  • Moving Targets
  • Optical Lattices
  • Ordnance Laboratories
  • Simulators
  • Turbulence
  • Wind Velocity

Fields of Study

  • Physics

Readers

  • Optical Physics and Photonics.