Open AccessWave optics simulation of atmospheric turbulence and reflective speckle effects in CO{sub 2} differential absorption LIDAR (DIAL)
Author(s) -
D.H. Nelson,
R.R. Petrin,
E.P. MacKerrow,
M.J. Schmitt,
C.R. Quick,
A. Zardecki,
W.M. Porch,
M. Whitehead,
D.L. Walters
Publication year - 1998
Language(s) - English
Resource type - Reports
DOI - 10.2172/674893
Subject(s) - dial , speckle pattern , scintillation , optics , lidar , atmospheric optics , turbulence , physics , atmospheric turbulence , physical optics , meteorology , acoustics , detector
The measurement sensitivity of CO{sub 2} differential absorption LIDAR (DIAL) can be affected by a number of different processes. The authors address the interaction of two of these processes: effects due to beam propagation through atmospheric turbulence and effects due to reflective speckle. Atmospheric turbulence affects the beam distribution of energy and phase on target. These effects include beam spreading, beam wander and scintillation which can result in increased shot-to-shot signal noise. In addition, reflective speckle alone has a major impact on the sensitivity of CO{sub 2} DIAL. The interaction of atmospheric turbulence and reflective speckle is of great importance in the performance of a DIAL system. A Huygens-Fresnel wave optics propagation code has previously been developed at the Naval Postgraduate School that models the effects of atmospheric turbulence as propagation through a series of phase screens with appropriate atmospheric statistical characteristics. This code has been modified to include the effects of reflective speckle. The performance of this modified code with respect to the combined effects of atmospheric turbulence and reflective speckle is examined. Results are compared with a combination of experimental data and analytical models