Linear theory of thermal blooming in turbulence.

摘要

In this paper we show how the electric field spectrum for a high energy laser beam propagating through a uniform atmosphere can be calculated using the linear theory of small fluctuations. The beam is modeled analytically as an infinite plane wave which propagates through a medium with constant absorption and no transverse wind. Return-wave phase compensation is modeled as a filter in the transverse wind. Return-wave phase compensation is modeled as a filter in the transverse Fourier domain. The linear theory describes the growth of small fluctuations on the beam and accurately predicts the evolution of the electric field spectrum until the magnitude of the fluctuations approach the original beam irradiance. The accuracy is tested by comparing with the spectrum calculated using ORACLE, a full wave optics thermal blooming code. 4 refs., 3 figs.