In recent research, anisoplanatic electromagnetic (EM) wave propagation along a slanted path in the presence
of low atmosphere phase turbulence (modified von Karman spectrum or MVKS) has been investigated
assuming a Hufnagel-Valley (HV) type structure parameter. Preliminary results indicate a strong dependence
on the slant angle especially for long range transmission and relatively strong turbulence. The investigation
was further divided into two regimes, viz. (a) one where the EM source consisted of a plane wave modulated
with a digitized image, which is propagated along the turbulent path and recovered via demodulation at the
receiver; and (b) transmit the plane wave without modulation along the turbulent path through an image
transparency and a thin lens designed to gather the received image in the focal plane. In this paper, we reexamine
the same problem (part (a) only) in the presence of a chaotic optical carrier where the chaos is
generated in the feedback loop of an acousto-optic Bragg cell. The image information is encrypted within the
chaos wave, and subsequently propagated along a similar slant path and identical turbulence conditions. The
recovered image extracted via heterodyning from the received chaos is compared quantitatively (through
image cross-correlations and mean-squared error measures) for the non-chaotic versus the chaotic approaches.
Generally, “packaging” the information in chaos improves performance through turbulent propagation, and
results are discussed from this perspective. Concurrently, we will also examine the effect of a non-encrypted
plane EM wave propagation through a transparency-lens combination. These results are also presented with
appropriate comparisons with the cases involving lensless transmission of imagery through corresponding
turbulent and non-turbulent layers.
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