  Utilization of chaotic signals for covert communications remains a very
promising practical application. Multiple studies indicated that the major
shortcoming of recently proposed chaos-based communication schemes is their
susceptibility to noise and distortions in communication channels. In this talk
we discuss a new approach to communication with chaotic signals, which
demonstrates good performance in the presence of channel distortions. This
communication scheme is based upon chaotic signals in the form of pulse trains
where intervals between the pulses are determined by chaotic dynamics of a
pulse generator. The pulse train with chaotic interpulse intervals is used as a
carrier. Binary information is modulated onto this carrier by the pulse
position modulation method, such that each pulse is either left unchanged or
delayed by a certain time, depending on whether ``0'' or ``1'' is transmitted.
By synchronizing the receiver to the chaotic pulse train we can anticipate the
timing of pulses corresponding to ``0'' and ``1'' and thus can decode the
transmitted information. Based on the results of theoretical and experimental
studies we shall discuss the basic design principles for the chaotic pulse
generator, its synchronization, and the performance of the chaotic pulse
communication scheme in the presence of channel noise and filtering.
