Unravelling dependencies on turbulence strength and propagation geometry in models of optical scintillation.
Abstract
Scintillation of a light propagating through atmospheric turbulence can be modeled either via analytic approaches or numerical simulations. However, predictions between these two approaches can differ by a factor of two or more in specific cases. Analytical approaches rely on approximations to the stochastic Helmholtz equation and are most tractable in weak turbulence or asymptotically as intensity fluctuations saturate. Extended Rytov Theory (ERT) attempts to bridge these two regions to predict scintillation in the focusing regime where intensity scintillations are strongest. However, ERT produces different results when turbulence strength or propagation distance are varied independently for the same volume turbulence strength. Numerical simulation using thin phase screens can provide an exact solution provided they are properly configured. To resolve real or perceived differences, I propose quantifying the uncertainty resulting from reasonable misconfiguration of wave optics simulations via a limited simulation campaign. It is also clear that ERT includes an unstated scale dependence proportional to the size of the first Fresnel zone. I further propose decoupling propagation geometry and turbulence strength in ERT as a reformulation. A related simulation campaign will independently explore the effect of propagation geometry on the interplay between geometry, turbulence strength, turbulence spectral properties.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2024
- Source ID
- FA95502310623
Entities
People
- Jeremy P. Bos
Organizations
- Air Force Office of Scientific Research
- Michigan Technological University
- United States Air Force