Extracting periodic driving signal from chaotic noise  

作　　者：MU Jing , TAO Chao and DU Gonghuan(State Key Laboratory of Modern Acoustics and Institute of Acoustics, Nanjing University, Nanjing 210093, China) 

出　　处：《Progress in Natural Science:Materials International》2003年第9期666-671,共6页自然科学进展·国际材料（英文版）

基　　金：Supported by the National Natural Science Foundation of China (Grant Nos.10074035 and 19834040)

摘　　要：After periodic signals pass through some nonlinear systems, they are usually transformed into noise-like and wide-band chaotic signals. The discrete spectrums of the original periodic signals are often covered by the chaotic spectrums. Recovering the periodic driving signals from the chaotic signals is important not only in theory but also in practical applications. Based on the modeling theory of nonlinear dynamic system, a 'polynomial-simple harmonic drive' non-autonomous equation (P-S equation) to approximate the original system is proposed and the approximation error between P-S equation and the original system is obtained. By changing the drive frequency, we obtain the curve of the approximation error vs. drive frequency. Based on the relation between this curve and the spectrums of the original periodic signals, the spectrum of the original driving signal is extracted and the original signal is recovered.After periodic signals pass through some nonlinear systems, they are usually transformed into noise-like and wide-band chaotic signals. The discrete spectrums of the original periodic signals are often covered by the chaotic spectrums. Recovering the periodic driving signals from the chaotic signals is important not only in theory but also in practical applications. Based on the modeling theory of nonlinear dynamic system, a ' polynomial-simple harmonic drive' non-autonomous equation (P-S equation) to approximate the original system is proposed and the approximation error between P-S equation and the original system is obtained. By changing the drive frequency, we obtain the curve of the approximation error vs. drive frequency. Based on the relation between this curve and the spectrums of the original periodic signals, the spectrum of the original driving signal is extracted and the original signal is recovered.

关 键 词：non-autonomous system CHAOS chaotic noise. 

分 类 号：O423[理学—声学]