小波包分析提取振动信号中的特征频率，sar图像去噪的几种新的方法，IMC-PID是利用内模控制原理来对PID参数进行计算。- Wavelet packet analysis to extract vibration signal characteristic frequency, Several new methods sar image denoising, The IMC- PID is using the internal model control principle for PID parameters is calculated.