Propagation in random media with stationary temporal fluctuations
Abstract
Born's method is applied to the timedependent wave equation. Exact solutions, valid for all wavelengths, are obtained for the firstorder perturbation terms for monochromatic plane and spherical waves propagating in random media with stationary temporal fluctuations. It is shown that the temporal fluctuations of the medium can be neglected if the temporal frequencies of the fluctuations are much less than the frequency of the propagating wave and if the propagation time from the transmitter to receiver is much less than the coherence time of the medium. In the atmosphere for the case where (λ^{3}_{0}/l^{4}_{0})L≪ 1, where l_{0} is the inner scale of turbulence, logamplitude and phase covariance functions were calculated for the polarized and depolarized fluctuations of plane waves propagating in slightly different directions. Numerical evaluation revealed that the polarized logamplitude fluctuations decorrelate for angular separations on the order of tan^{1} [(λ^{0}/L)^{1/2}] while phase fluctuations decorrelate for angular separations on the order of tan^{l}(L_{0}/L), where L_{0} is the outer scale of turbulence.
 Publication:

Radio Science
 Pub Date:
 November 1975
 DOI:
 10.1029/RS010i011p00979
 Bibcode:
 1975RaSc...10..979G
 Keywords:

 Born Approximation;
 Random Processes;
 Time Dependence;
 Wave Equations;
 Wave Propagation;
 Covariance;
 Light Emission;
 Monochromatic Radiation;
 Numerical Analysis;
 Phase Shift;
 Plane Waves;
 Spherical Waves;
 Communications and Radar