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Mitigation of image distortion under modified von Karman-type phase turbulence has been examined by using acousto-optic (A-O) chaos waves generated via feedback in a Bragg cell. The chaos wave transferred to the optical carrier either over an image-bearing transparency (with the image reconstructed with appropriate lensing), or alternatively the two-dimensional image (both static as well as dynamic) is embedded in the chaos wave and propagated over the turbulent layer. These investigations demonstrate that the properties of chaos waves including relative immunity from variations in the propagation path enable reduction or mitigation of the image distortion under turbulent conditions. Mitigation of image distortion is explored using propagation through a turbulent atmospheric layer characterized by gamma–gamma type intensity fluctuations. Standard weak, moderate, and strong turbulence conditions are applied for the numerical analysis based on the corresponding structure parameters. Following standard approach, the relevant probability density functions are generated using small- and large-scale eddies (α and β numbers) incorporated into the turbulence model. In addition, mitigation of image distortion due to gamma–gamma turbulence is examined for propagation along a low-altitude slanted path with a fixed slope and different elevation angles using A-O chaos along with the Huffnagel–Valley model. Stationary images are transmitted under nonchaotic and chaotic conditions, and the corresponding distortions in the received images are measured using the conventional metric of bit error rates. The system performances under nonchaotic and chaotic transmissions are compared with the intent to establish that packaging a signal within a chaos wave offers a degree of distortion mitigation.
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