title: Probability density of irradiance fluctuations observed over terrestrial ranges.
abstract: The irradiance fluctuations imposed on a laser beam that has propagated over horizontal terrestrial paths in the range of 2 to 24 km are compared to lognormal (LN) and gamma-gamma (GG) distributions. For the direct links reported here the irradiance fluctuations follow a LN distribution except in cases of weak turbulence, characterized by a scintillation index of less than 1 and a Fried parameter larger than the receiver aperture, in which case the GG distribution gives an improved fit. In very weak turbulence the difference between the two distributions is insignificant.
authors.affiliation: Code 5654, Naval Research Laboratory, Overlook Ave, SW Washington, DC 20375, USA. rita.mahon@nrl.navy.mil
authors.forename: Rita
authors.initials: R
authors.lastname: Mahon
authors.forename: Christopher I
authors.initials: CI
authors.lastname: Moore
authors.forename: Harris R
authors.initials: HR
authors.lastname: Burris
authors.forename: Mike
authors.initials: M
authors.lastname: Ferraro
authors.forename: William S
authors.initials: WS
authors.lastname: Rabinovich
authors.forename: Michel
authors.initials: M
authors.lastname: Suite
authors.forename: Linda M
authors.initials: LM
authors.lastname: Thomas