Using filters for chaotic synchronization for communications

There have been many proposals recently to use synchronized chaotic systems for communications, but the problems of actually sending chaotic signals in a noisy environment, altering the spectral properties of chaos, and resisting unmasking have yet to be solved. In this work, it is shown that a chaotic carrier signal may be filtered and transmitted to a receiver where the carrier signal is reconstructed by a process that does not involve any inversions. This technique allows (1) engineering of the spectral properties of the chaotic signal (2) communications via chaotic carrier in the presence of noise (3) the separation of multiple information-carrying chaotic signals with overlapping frequency spectra.