NASA Logo, External Link
Facebook icon, External Link to NASA STI page on Facebook Twitter icon, External Link to NASA STI on Twitter YouTube icon, External Link to NASA STI Channel on YouTube RSS icon, External Link to New NASA STI RSS Feed AddThis share icon
 

Record Details

Record 6 of 7257
Laser beam propagation in atmospheric turbulence
Author and Affiliation:
Murty, S. S. R.(Alabama A & M University, Normal, Ala., United States)
Abstract: The optical effects of atmospheric turbulence on the propagation of low power laser beams are reviewed in this paper. The optical effects are produced by the temperature fluctuations which result in fluctuations of the refractive index of air. The commonly-used models of index-of-refraction fluctuations are presented. Laser beams experience fluctuations of beam size, beam position, and intensity distribution within the beam due to refractive turbulence. Some of the observed effects are qualitatively explained by treating the turbulent atmosphere as a collection of moving gaseous lenses of various sizes. Analytical results and experimental verifications of the variance, covariance and probability distribution of intensity fluctuations in weak turbulence are presented. For stronger turbulence, a saturation of the optical scintillations is observed. The saturation of scintillations involves a progressive break-up of the beam into multiple patches; the beam loses some of its lateral coherence. Heterodyne systems operating in a turbulent atmosphere experience a loss of heterodyne signal due to the destruction of coherence.
Publication Date: May 01, 1979
Document ID:
19800037762
(Acquired Nov 30, 1995)
Accession Number: 80A21932
Subject Category: LASERS AND MASERS
Document Type: Journal Article
Publisher Information: India
Contract/Grant/Task Num: NSG-8037
Financial Sponsor: NASA; United States
Organization Source: Alabama A & M Univ.; Normal, AL, United States
Description: 17p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
NASA Terms: ATMOSPHERIC OPTICS; ATMOSPHERIC TURBULENCE; LASER BEAMS; REFRACTIVITY; ATMOSPHERIC MODELS; COHERENT RADIATION; HETERODYNING; ISOTROPIC TURBULENCE; MATHEMATICAL MODELS; SCINTILLATION; TEMPERATURE EFFECTS; WAVELENGTHS
Imprint And Other Notes: Indian Academy of Sciences, Proceedings, Section C: Engineering Sciences, vol. C 2, May 1979, p. 179-195.
Availability Source: Other Sources
› Back to Top
Find Similar Records
NASA Logo, External Link
NASA Official: Gerald Steeman
Site Curator: STI Program
Last Modified: August 16, 2011
Contact Us