Performance improvement of chaotic encryption via energy and frequency location criteria

• Synchrony is verified by the convergence of the synchronization error system.
• The coupling strength was obtained from the synchronization error system.
• Selection criteria based on energy and spectral characteristics are proposed.
• The selection of the chaotic signal was improved by the criteria proposed.
• The encryption, transmission and retrieval using chaotic signals were performed.

Using a multi-scroll oscillator with an adjustable number of scrolls as chaos generator, this paper shows how an adequate control of the chaotic masking signal provides the basis for an improved security in private communication. We base the selection of the masking signal on two criteria related, respectively, to the energy and the spectral location of the signals in the complex synchronization network. The result is a successful encryption, transmission and retrieval of a confidential message in a two-channel communication system with multi-user modality.