Although often simple in design, chaotic systems produce signals of surprising complexity, facilitating several applications in cryptography. In this work, we present an experimental demonstration of one such application—a chaotic oscillator circuit (transmitter) for encryption of audio signals and another chaotic oscillator (receiver) synchronized to the transmitter via a linear feedback controller for signal decryption. All circuits are realized through operational amplifier (op-amp) chips connected on a breadboard, which makes this demonstration suitable for an undergraduate lab experiment that illustrates several interesting concepts, including nonlinear dynamics, chaos, encryption, and feedback control.
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