Architecture for Secure Communications Based on Chaotic Signals

Based on our currently developed methods for inband masking of information-bearing signals, which provide private communications of quite a different type than presently available for military or commercial use, we propose to explore these techniques with the intention of increasing both information bandwidth and security. The main idea of the method is to inject the information-bearing message into an appropriate port of a nonlinear chaotic signal generator--either a softrware or hardware device--and transmit the resulting masked signal through a communications channel to a receiver whose configuration is "identical" to that of the first nonlinear chaotic signal generator. Using the known structure in phase space of the signal generators, we are able to unmask the information-bearing signal with rather hgh fidelity using no further signal processing. However, since signals encoded using our techniques are highly unstable throughout the state space, "non-identical" receivers will yield huge errors in estimating the messge content.