Secure communication using chaotic synchronization
Philip T. Downes · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1993
Secure communication via chaotic synchronization of homogeneous driving systems of the Lorentz and Rossler type is demonstrated for AM, FM, SSB, and FSK modulations. Signal injection is additive. Actual AM, FM, SSB, and FSK signals were digitized using a 1 and 10 Mhz A/D. Analysis techniques of post chaotic modulation include the power spectrum, information dimension, Lyapunov exponents, mutual information, and metric entropy. Further inspection of the rates of convergence of the receiver subsystems gives insight into the selection of signal to driving system power ratio. Power ratios for adequate embedding for each modulation type in the chaotic signal are discussed. Differences in demodulation accuracy for the Lorentz and Rossler systems are discussed. It is seen that all modulation types can be sufficiently masked using a range of power ratio settings. However, the dynamical fidelity of the demodulated signal is compromised for some cases.