Numerical Simulation of Optical Turbulence Utilizing Two-Dimensional Gaussian Phase Screens
Abstract
Propagation of electromagnetic energy through the atmosphere is difficult task because of temperature fluctuations and index of refraction inhomogeneities which degrade the beam's coherence. Understanding this phenomena is of practical importance for optical systems. This thesis presents an analytical numerical technique which simulates the effects of atmospheric turbulence. The extended Huygens-Fresnel principle was used to simulate wave propagation in a two-dimensional randomly varying medium, which is represented by thin, filtered, Gaussian phase screens. The wave optics code implements both Fresnel and Fraunhofer propagation, by employing the fast Fourier transform (FFT) algorithm. The analytical spatial coherence length, rho sub 0, and normalized intensity variance, sigma-sq/I-sq, of the perturbed electric field, were examined. Results support the concept of intensity saturation for weak scattering cases, however, differences in the values of the theoretical and analytical spatial coherence lengths, occurred. Keywords: Atmospheric optical turbulence; Coherence length; Mutual coherence function; Saturation; Huygens Fresnel principle; Theses.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1989
- Accession Number
- ADA209436
Entities
People
- Elizabeth A. Ugorcak
Organizations
- Naval Postgraduate School