Atmospheric compensation with a speckle beacon in strong scintillation conditions: Directed energy and laser communication applications

Intelligent Optics Laboratory, Institute for Systems Research, University of Maryland, College Park, Maryland 20742, USA.
Applied Optics (Impact Factor: 1.78). 11/2005; 44(30):6388-401. DOI: 10.1364/AO.44.006388
Source: PubMed


Wavefront control experiments in strong scintillation conditions (scintillation index, approximately equal to 1) over a 2.33 km, near-horizontal, atmospheric propagation path are presented. The adaptive-optics system used comprises a tracking and a fast-beam-steering mirror as well as a 132-actuator, microelectromechanical-system, piston-type deformable mirror with a VLSI controller that implements stochastic parallel gradient descent control optimization of a system performance metric. The experiments demonstrate mitigation of atmospheric distortions with a speckle beacon typical for directed energy and free-space laser communication applications.

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