Mutual Coherence Function and Frequency Spectrum of a Laser Beam Propagating Through Atmospheric Turbulence.
Abstract
The mutual coherence function of a laser beam propagating in turbulence with a modified von Karman spectrum for the index of refraction fluctuations, including a parametric study of the effect on the MCF of varying beam size, focal length, and the properties of the turbulence was computed. The results are valid over all propagation distances, unlike calculations employing the method of smooth perturbations. Also studied was the effect of a constant wind on the frequency spectrum of signal. It was found that over most practical path lengths the spectral width is delta omega = 4.1V ((k sub o)sup 6/5)(z sup 3/5)((C sub n,sub 2)sup 3/5), where V is the wind speed, k sub o is the signal wavenumber, C sub n sup 2 is the strength of turbulence, and z is the path length in the turbulence. (Modified author abstract)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 06, 1974
- Accession Number
- AD0781039
Entities
People
- Ronald L. Fante
Organizations
- Air Force Cambridge Research Laboratories