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Updated: May 30, 2026

Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing
Published on: February 13, 2018
Bulk wind estimation and prediction for adaptive optics control systems
Luke C Johnson1, Donald T Gavel, Donald M Wiberg
1Center for Adaptive Optics, University of California, 1156 High Street, Santa Cruz, California 95064, USA. ljohnson@ucolick.org
Abstract:
We present a wind-predictive controller for astronomical adaptive optics (AO) systems that is able to predict the motion of a single windblown layer in the presence of other, more slowly varying phase aberrations. This controller relies on fast, gradient-based optical flow estimation to identify the velocity of the translating layer and a recursive mean estimator to account for turbulence that varies on a time scale much slower than the operating speed of the AO loop. We derive the Cramer-Rao lower bound for the wind estimation problem and show that the proposed estimator is very close to achieving theoretical minimum-variance performance. We also present simulations using on-sky data that show significant Strehl increases from using this controller in realistic atmospheric conditions.
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