Wind profiling based on the optical beam intensity statistics in a turbulent atmosphere

Abstract

Reconstruction of the wind profile from the statistics of intensity fluctuations of an optical beam propagating in a turbulent atmosphere is considered. The equations for the spatiotemporal correlation function and the spectrum of weak intensity fluctuations of a Gaussian beam are obtained. The algorithms of wind profile retrieval from the spatiotemporal intensity spectrum are described and the results of end-to-end computer experiments on wind profiling based on the developed algorithms are presented. It is shown that the developed algorithms allow retrieval of the wind profile from the turbulent optical beam intensity fluctuations with acceptable accuracy in many practically feasible laser measurements set up in the atmosphere.

Reconstruction of the wind velocity profile from the intensity fluctuations of a reflected spherical wave in the turbulent atmosphere

“…is the fourth statistical moment of the random component of the Green's function which we will seek by analogy with [6,7] assuming that the relative variance of the intensity fluctuations does not exceed unity and describing the spatiotemporal variations of the dielectric permittivity field using the Taylor hypothesis of frozen turbulence [12] (…”

“…(19) is reduced to the spherical wave intensity spectrum on the forward propagation path [7] if we replace the direction of propagation by the opposite one. Let us assume that the refractive index fluctuations are described by the Kolmogorov spectrum 11/ 3 ( ) 0.033 n − Φ κ = κ [13], and the Gaussian approximation…”

“…Correlation function (28) differs from that for the spherical wave intensity on the direct propagation path [7] only by the factor…”

“…In [5], the problem of reconstructing the wind velocity profiles from the wave field registered with wavefront sensors was considered. A method for reconstructing the wind velocity based on the correlation and spectral analysis of the intensity fluctuations was suggested in [6,7].…”

“…In the present article, the possibilities of reconstructing the wind velocity profiles from turbulent intensity fluctuations of optical radiation propagating in the atmosphere on the path with reflection is studied based on the approach suggested in [6,7]. Expressions for the spatiotemporal correlation function for the radiation intensity and its Fourier spectrum are derived.…”