含噪声混沌信号的小波去噪方法研究

Studying on Denoising of Chaotic Signal Using Wavelet Transform

基于混沌信号具有分形结构的特点，提出了一种分数维与小波变换相结合的带观测噪声混沌信号的噪声去除新方法，利用噪声小波变换特性提取信号的真实分数维，进而根据欲处理混沌时间序列分数维与信号真实分数维之差控制小波包除噪的阈值及位置，达到噪声与信号的自适应分离。该方法克服了以往对未知动力系统方程信号除噪的盲目性，仿真结果表明此法有效可行。

In this paper a new method was proposed to reduce noise within chaotic signal based on wavelet transform and fractal theory. The chaotic signal has the fractal characteristic, its fractal dimension of noisy signal can be calculated and can be used to control the threshold and location of wavelet packet transform. This method provided a useful criterion for reducing noise of unknown dynamic system equation. The results show that it is practicable and effective for reducing noise within chaotic signal.