Analysis of Chaotic System Characters Based on Time-Frequency Distribution

Chaotic signal is non-stationary when chaos system is in chaotic state. Wigner distribution (WD) is one of time-frequently distribution methods. This paper analyzed the characters of chaos system and the energy of output signal. Simulation experiment indicated that chaos system is a narrowband system, because the frequency band of the output signal became narrower, which showed that it can fully suppress the signal outside inherent frequency. At the same time, the WD of chaos signal and random signal were analyzed respectively by time-frequently distribution. The problem, which the two signals are difficult to be distinguished by correlation method and spectrum method, now is deal with successfully. In this paper, the narrowband character of chaos system proposed offer a new way and method for detecting weak signal in strong noise