You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither SPIE nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the SPIE website.
20 June 2001Double-pass fade statistics of a laser beam under moderate to strong atmospheric turbulence
For a Gaussian-beam wave incident on a point target, we use a recently developed scintillation theory and the gamma- gamma probability density function to calculate the fade statistics of the echo wave as a function of threshold below the mean irradiance. We also compare the results with experimental data collected by a coherent receiver array over a 1-km propagation path to the target using from one to eight apertures of the array. The propagation channel was determined to be a bistatic configuration for the lidar system. Values of inner scale and refractive index structure constant were simultaneously measured during the experiment by use of a scintillometer instrument. The scintillation theory employed in this work utilizes a spatial filter function that results from adapting a modulation scheme in which it is assumed that the intensity of the propagating laser beam is a product of two quantities: one related to the large scale turbulent eddies of the atmosphere and the other related to the small scale eddies. The theoretical curves arising from this analysis provide a good fit with experimental data up to four active apertures of the array, but deviate somewhat from the data for a greater number of apertures.
The alert did not successfully save. Please try again later.
Ammar Al-Habash, Larry C. Andrews, Ronald L. Phillips, "Double-pass fade statistics of a laser beam under moderate to strong atmospheric turbulence," Proc. SPIE 4272, Free-Space Laser Communication Technologies XIII, (20 June 2001); https://doi.org/10.1117/12.430787