Title :
Effects of turbulence on laser beam position
Author :
Verraneault, Ronald E. ; Arora, Rajendra K.
Author_Institution :
Dept. of Electr. & Comput. Eng., Florida A&M Univ., Tallahassee, FL, USA
Abstract :
If a laser beam travels through a medium with constant refractive index, then the travel path will be a straight line from source to receiver. If the medium does not have a constant refractive index, then the beam will be diffracted. The lower atmosphere represents this latter case since temperature gradients near the Earth´s surface generate turbulence that results in random fluctuation in the refractive index of the atmosphere. As a consequence, a laser beam traveling through the lower atmosphere will be diffracted from the intended target. This diffraction is a random phenomenon that is difficult to model and must be analyzed using statistical tools. By using a heated water column to simulate the lower atmosphere, this research has shown that turbulence based models can be improved by first establishing a reference that is used for comparison and statistical purposes
Keywords :
atmospheric light propagation; atmospheric turbulence; laser beams; light diffraction; refractive index; Earth surface; heated water column; laser beam diffraction; lower atmosphere; random fluctuation; refractive index; statistical model; temperature gradient; turbulence; Atmosphere; Atmospheric modeling; Diffraction; Earth; Fluctuations; Laser beams; Laser modes; Refractive index; Temperature; Water heating;
Conference_Titel :
Digital Avionics Systems, 2001. DASC. 20th Conference
Conference_Location :
Daytona Beach, FL
Print_ISBN :
0-7803-7034-1
DOI :
10.1109/DASC.2001.964218