用matlab如何实现fft变换

matlab计算haar 小波各级近似系数和细节系数的频率响应（CA1，CD1，CA2，CD2，CA3），并画出幅频图，便于理解小波变换的意义，(U191 u7197 u5c1 u5c1 u5Fc1 u4Fc u653 u564C u548C u7286 u8282 u7CFB u6570 u7684 u9891 u54CD u5E94 uFF08CA1 uFF0CCD1 uFF0CCA2 uFF0CCD2 UFF0CCA3 uFF09 uFF0C u5E76 u753B u51FA u5E45 u9891 u56FE uFF0C u4FBF u4E8E u7406 u89E3 u5C0F u6CE2 u53D8 u6362 u7684 u610F u4E49 uFF0C)

说明：  Fault Location in Extra Long HVdc Transmission Lines using Continuous Wavelet Transform

离散小波变换程序 实现了4层离散小波变换 可运行的程序代码(The discrete wavelet transform procedure achieved a 4-layer discrete wavelet transform operable program code)

基于matlab的小波包分解应用于机械振动信号的故障分析(Used in failure analysis of mechanical vibration signals based on the Matlab wavelet packet decomposition)

本程序用Mallat算法实现小波变换,方法简答以实现(This program uses the mallat algorithe to implement wavelet transform)

心电信号的预处理。高通滤波器，低通滤波器，50Hz带阻滤波器。(The preprocessing of the ECG signal. High-pass filter, low pass filter, 50Hz band-stop filter....)

说明：  关于小波变换的一些常用函数，有关多尺度变换，希望可以帮助您(Wavelet commonly used functions, on multi-scale transformation, I hope to help you)

相关性小波去噪的程序实现，相关性去噪的程序实现(Wavelet denoising procedures related implementation procedures related to implementation of denoising)

利用matlab中的小波变换函数，对图像进行小波降噪，并分析降噪效果。(The wavelet transform using matlab function, the image wavelet noise reduction, and analyze the noise reduction effect.)

说明：  ecg信号处理，基线漂移，小波变换、snr mse(ECG signal processing, baseline drift, wavelet transform, SNR MSE)