The Aggregate Behavior of Branch Points - Branch Point Density as a Characteristic of an Atmospheric Turbulence Simulator (postprint)
Abstract
The atmospheric turbulence simulator used in testing in the atmospheric simulation and adaptive-optic laboratory test-bed at Starfire Optical Range is configured based on three characteristics: Fried's parameter, the Rytov number and the Greenwood Frequency. All three may be estimated from open loop data as a means of verifying the simulated turbulence conditions for a given test configuration. However, unlike Fried's parameter and the Greenwood Frequency the Rytov number isn't directly calculated. Instead the scintillation index is estimated from intensity measurements. At low Rytov values, (<0.3-0.4), this measurement can approximate the Rytov number; however beyond a Rytov of 0.4 this parameter becomes saturated. Branch Points begin to appear after the Rytov value exceeds 0.1. In this work the behavior of branch point density is examined to determine its viability as another parameter for calibration our turbulence simulator.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2009
- Accession Number
- ADA517293
Entities
People
- Carolyn M. Tewksbury-christle
- Darryl J. Sanchez
- Denis W. Oesch
- Patrick R. Kelly
Organizations
- Air Force Research Laboratory