Portal de Periódicos da CAPES

AAOL wavefront data reduction approaches

2012; SPIE; Volume: 8395; Linguagem: Inglês

10.1117/12.922838

1996-756X

Shaddy Abado, Stanislav Gordeyev, Eric Jumper,

Meteorological Phenomena and Simulations

This paper addresses a method for extracting the convection speed and direction of aberrations present in wavefronts due to aero-optical turbulence over the pupil of a turret on the side of an airborne platform. The method is applied to data from the Airborne Aero-Optics Laboratory (AAOL). Such convection information is useful in designing feed-forward adaptive-optic approaches. The method makes use of a four-beam Malley probe technique derived by constructing a two-dimensional local convective velocity-distribution over the beam's aperture. This technique is based on extending the analysis of the Notre-Dame-developed Malley probe. Two wavefront datasets (Azimuth 157° and Elevation 40°; Azimuth 42° and Elevation 43°) from the AAOL are analyzed using the derived method, the first where the laser propagates through fully-separated flow and the second where the laser propagates through an attached-flow region. Finally, the two-dimensional Proper Orthogonal Decomposition is applied to one in-flight measured dataset to determine the spatial requirements of deformable mirrors in an adaptive-optics system. The paper concludes with a discussion that points out the usefulness of the two-dimensional velocity-distributions in characterizing the various flow structures which convect over the aperture.