Irradiance data were collected over an air-to-ground path using several different sized receiving apertures. The data were collected from the Optical RF Communications Adjunct (ORCA) tracking beacon. The receiver system consisted of three telescopes of sizes 51 mm, 137 mm, and 272 mm. Probability of fade, number of fades per second, and mean fade time was computed for various intensity levels for irradiance data collected on all three telescopes. These measured statistics are compared to fading models derived from lognormal and gamma-gamma probability density function (PDF) models. Discussion is centered on the viability of these models under various conditions and on the presence of aero-optic effects. The gamma-gamma and lognormal model are found to be insufficient to model all fading statistics.

Date Published: 25 May 2011
PDF: 11 pages
Proc. SPIE 8038, Atmospheric Propagation VIII, 80380D (25 May 2011); doi: 10.1117/12.887997

Published in SPIE Proceedings Vol. 8038:
Atmospheric Propagation VIII
Linda M. Wasiczko Thomas; Earl J. Spillar, Editor(s)