Share Email Print

Proceedings Paper

Experimental study of spatial structure of turbulence at Maui Space Surveillance Site (MSSS)
Author(s): Mikhail S. Belen'kii; Edward Cuellar; Kevin A. Hughes; Vincent A. Rye
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

We investigated the spatial structure of atmospheric turbulence at Maui Space Surveillance Site (MSSS) using a 3.6 m telescope and a spatial filtering receiver. This receiver simultaneously records four star images on one camera frame. The star images are formed through pupil masks representing aperture diameters of 0.1 m, 0.5m, 1.5 m, and 3.6 m. We determined the camera orientation for each data set by moving the telescope at a given angle in azimuth and elevation. We calculated the horizontal and vertical components of the image centroid and evaluated the statistics of the horizontal and vertical wavefront tilt as a function of the aperture diameter and seeing conditions. We found several evidences of anisotropy of turbulence at MSSS. On four nights we observed that the variance of on-axis horizontal tilt exceeded the variance of the vertical tilt by a factor of 1.3-3.3. We believe that this is due to anisotropy of large-scale turbulence, where the horizontal scale of the turbulent inhomogeneities exceeds their vertical scale. The estimates of the horizontal and vertical turbulence outer scale confirmed this conclusion. In addition, in several data sets the horizontal image spot diameter of the long-exposure star image exceeded the vertical image spot diameter. We also found that large apertures are more likely to have higher anisotropy coefficient values than small apertures. This is because the contribution of small-scale isotropic turbulence to the image centroid reduces with increasing telescope diameter. In the case of isotropic turbulence, the power spectral densities (PSDs) of wavefront tilt are consistent with theoretical models. The telescope vibration modes were observed at 20 Hz. In the case of anisotropic turbulence, the PSDs of the horizontal tilt component have lower slope in the high frequency range, and difference between PSDs for large and small apertures is reduced. The anisotropy of turbulence and atmospheric tilt may affect the design and performance analysis of both active and passive optical systems.

Paper Details

Date Published: 1 September 2006
PDF: 12 pages
Proc. SPIE 6304, Free-Space Laser Communications VI, 63040U (1 September 2006); doi: 10.1117/12.679093
Show Author Affiliations
Mikhail S. Belen'kii, Trex Enterprises Corp. (United States)
Edward Cuellar, Trex Enterprises Corp. (United States)
Kevin A. Hughes, Trex Enterprises Corp. (United States)
Vincent A. Rye, Trex Enterprises Corp. (United States)

Published in SPIE Proceedings Vol. 6304:
Free-Space Laser Communications VI
Arun K. Majumdar; Christopher C. Davis, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?