matlab中小波滤波

Question

如何用matlab中的小波函数去除心电信号的噪声，求程序，函数也行，非常感谢

Answer 1

　　Matlab之小波滤波函数 :
　　1 wfilters函数
　　[Lo_D,Hi_D,Lo_R,Hi_R] = wfilters('wname') computes four filters associated with the orthogonal or biorthogonal wavelet named in the string 'wname'. The four output filters are
　　Lo_D, the decomposition low-pass filter Hi_D, the decomposition high-pass filter Lo_R, the reconstruction low-pass filter
　　Hi_R, the reconstruction high-pass filter
　　2 biorfilt函数
　　The biorfilt command returns either four or eight filters associated with biorthogonal wavelets.
　　3 orthfilt函数
　　[Lo_D,Hi_D,Lo_R,Hi_R] = orthfilt(W) computes the four filters associated with the scaling filter W corresponding to a wavelet
　　4 biorwaef函数
　　[RF,DF] = biorwavf(W) returns two scaling filters associated with the biorthogonal wavelet specified by the string W.
　　5 coifwavf函数
　　F = coifwavf(W) returns the scaling filter associated with the Coiflet wavelet specified by the string W where W = 'coifN'. Possible values for N are 1, 2, 3, 4, or 5
　　6 dbaux函数
　　W = dbaux(N,SUMW) is the order N Daubechies scaling filter such that sum(W) = SUMW. Possible values for N are 1, 2, 3, ...
　　W = dbaux(N) is equivalent to W = dbaux(N,1) W = dbaux(N,0) is equivalent to W = dbaux(N,1)
　　7 dbwavf函数
　　F = dbwavf(W) returns the scaling filter associated with Daubechies wavelet specified by the string W where W = 'dbN'. Possible values for N are 1, 2, 3, ..., 45.　　
　　8 mexihat函数
　　[PSI,X] = mexihat(LB,UB,N) returns values of the Mexican hat wavelet on an N point regular grid, X, in the interval [LB,UB].
　　Output arguments are the wavelet function PSI computed on the grid X. This wavelet has [-5 5] as effective support.

Answer 2

%以下为滤波程序（主要调节参数c的大小）
c=10;
wn=0.1;
fs=50000; %采样频率；
b=fir1(c,wn/(fs/2),hamming(c+1));
y1=filtfilt(b,1,y);%对y滤波本回答被提问者采纳