tired.asv

用matlab设计FIR和IIR滤波器的设计函数与例程

%实时检测QRS复波，采样率1000HZ
%filename='D:\数据\刘新光.mat';
%实时检测QRS复波，采样率1000HZ
filename='D:\数据\蔡刿.mat';
load(filename);
ecgdata=data(:,2);
ecg=ecgdata(1:2000);
%-------------------------------------
t=0.85;w=2*pi*50/fs;
b4=[1,-2*cos(0.33*pi),1]; a4=[1,-2*0.85*cos(0.33*pi),0.33*0.85];%60Hz窄带陷波器:60/180=1/3


M=fs/50;
%------------lp,截至频率11HZ，延迟5个采样点，增益36
a=[1 zeros(1,M-1) -2 zeros(1,M-1) 1];
b=[1 -2 1];
ecgdata_denoise=filter(a,b,ecg);
 figure(1);subplot(2,1,1);plot(ecg(1:1000));title('orignal');
subplot(2,1,2);
plot(ecgdata_denoise(1:1000));title('低通滤波，去除60hz');
 figure(2);
 freqz(a,b,512,fs);