MULTIWAVELENGTH LASER PROPAGATION STUDY--3
Quarterly rept. no. 1, 16 Jun-15 Sep 1970
OREGON GRADUATE CENTER FOR STUDY AND RESEARCH PORTLAND
Pagination or Media Count:
The report reviews activities in a comprehensive study of multiwavelength laser scintillations due to atmospheric turbulence. A large quantity of experimental data is being collected by means of repeated standard runs which include the determination of all pertinent properties of multiwavelength amplitude scintillations and turbulent structure. During the high turbulence conditions of the summer months, the spectrum of turbulence was found to agree with the 53 law with the existence of a well-defined inner scale. Also, scintillations have been strong at the 10.6 micron wavelength, where the transverse amplitude correlation length has been observed to be smaller than that for weaker turbulence. This improves the performance of aperture-averaging receivers at this important wavelength. The intermittency or spiking of turbulent temperature fluctuations was found to be a manifestation of the near log normality of the distribution of the absolute value of those fluctuations. The ramifications of this result are discussed.