Nonlinear Dynamics, Bifurcation Maps and Signal Encryption and Decryption Using Acousto-Optic Chaos Under a Variable Aperture Illumination

Abstract

The nonlinear dynamics (NLD) and bifurcation characteristics of a Bragg cell under first-order feedback are examined for a variable aperture. Corresponding chaotic encryption and recovery of low-bandwidth signals are examined for fixed (optimal) photodetector aperture (at about 73%), and subsequent sub-optimal aperture variation. Device performance and tolerances are evaluated and compared relative to the optimal fixed aperture, and the dynamical impact of the encryption system is evaluated in terms of possible variations in the photodetector illumination area. OCIS codes: (070.1060) acousto-optic signal processing; (060.4785) optical security & encryption; (190.3100) instabilities and chaos