資源簡介
zw_mamayu1314-9409158-Untitled.zip

代碼片段和文件信息
clear?all;close?all;
%繪制原始心電信號的時域圖和頻譜圖
ECG=load(‘C:\Users\Administrator\Desktop\renwushu\ecg101.txt‘);
time=ECG(:1);
amplitude=ECG(:2);
figure(1);
subplot(211);plot(timeamplitude);title(‘原始心電信號的時域圖‘);xlabel(‘時間/s‘);ylabel(‘幅值/mv‘);axis([010-3.53.5]);grid?on;
n=length(time);
an=fft(amplitude);
T=ceil(max(time));
Fs=n/T;
f=Fs/n*(0:n-1);
subplot(212);plot(fabs(an));title(‘原始心電信號的頻譜圖‘);xlabel(‘頻率/Hz‘);ylabel(‘|X(k)|‘);axis([0180-1400]);grid?on;
%?沖擊響應不變法設計IIR帶通濾波器設數字指標fp=[1?30]fst=[0.5?35]Rp=2As=5.
fp=[1?30];fst=[0.5?35];Rp=2;As=5;
Wp=fp*2*pi;Wst=fst*2*pi;
[N1Wc]=buttord(WpWstRpAs‘s‘);
[zpk]=buttap(N1);???[ba]=zp2tf(zpk);
W1=Wp(2)-Wp(1);???W2=sqrt(Wp(1)*Wp(2));
[bsas]=lp2bp(baW2W1);
[bzaz]=impinvar(bsasFs);
[H1w1]=freqz(bzazFs);
f1=w1/pi*Fs/2;?
figure(2);
subplot(211);plot(f120*log10(abs(H1)));title(‘IIR帶通濾波器幅頻特性‘);xlabel(‘頻率/Hz‘);ylabel(‘20log10|H1(K)|‘);grid?on;
subplot(212);plot(f1angle(H1));title(‘IIR帶通濾波器相頻特性‘);xlabel(‘頻率/Hz‘);ylabel(‘arg[H1(K)]‘);grid?on;
figure(3)
h1=impz(bzaz);
subplot(211);?plot(h1);title(‘IIR帶通濾波器的單位抽樣響應‘);xlabel(‘n‘);ylabel(‘h1‘);grid?on;
%IIR帶通濾波器濾波之后
figure(4)
y1=filter(bzazECG(:2));
subplot(211);plot(timey1);title(‘IIR帶通濾波器濾波后心電信號的時域圖‘);xlabel(‘時間/s‘);ylabel(‘幅值/mv‘);axis([010-3.53.5]);grid?on;
subplot(212);plot(fabs(fft(y1)));title(‘IIR帶通濾波器濾波后心電信號的頻譜圖‘);xlabel(‘頻率/Hz‘);ylabel(‘|Y1(k)|‘);axis([0180-1400]);grid?on;
%窗函數法設計FIR高通濾波器設fp=0.3fs=0.8As=5選用矩形窗.
wp=2*pi*0.3/Fs;ws=2*pi*0.8/Fs;dw=ws-wp;
N2=ceil(1.8*pi/dw)?;
if?rem(N22)==0???????
????N2=N2+1;
end
wc=(ws+wp)/2;
window=boxcar(N2);
h2=fir1(N2-1wc‘high‘window);
figure(5)
[H2w2]=freqz(h21);?
f2=w2/pi*Fs/2;?
subplot(211);plot(f220*log10(abs(H2)));title(‘FIR高通濾波器幅頻特性‘);xlabel(‘頻率/Hz‘);ylabel(‘20log10|H(K)|‘);grid?on;
subplot(212);plot(f2angle(H2));title(‘FIR高通濾波器相頻特性‘);xlabel(‘頻率/Hz‘);ylabel(‘arg[H(K)]‘);grid?on;
figure(6)
subplot(211);?plot(h2);title(‘FIR高通濾波器的單位抽樣響應‘);xlabel(‘n‘);ylabel(‘h2‘);grid?on;
%FIR高通濾波器濾波之后
figure(7)
y2=filter(h21ECG(:2));
subplot(211);plot(timey2);title(‘FIR高通濾波器濾波后心電信號的時域圖‘);xlabel(‘時間/s‘);ylabel(‘幅值/mv‘);axis([010-3.53.5]);grid?on;
subplot(212);plot(fabs(fft(y2)));title(‘FIR高通濾波器濾波后心電信號的頻譜圖‘);xlabel(‘頻率/Hz‘);ylabel(‘|Y2(k)|‘);axis([0180-1400]);grid?on;
%對原信號2倍插值
figure(8)
x=0:n-1;
y=ECG(:2);
xi=0:0.5:n-1;
yi_linear=interp1(xyxi);
t=10/3600*xi;
subplot(211);plot(tyi_linear);title(‘2倍插值心電信號的時域圖‘);xlabel(‘時間/s‘);ylabel(‘幅值/mv‘);axis([010-3.53.5]);grid?on;
n2=2*n;
y2=fft(yi_linearn2);
Fs2=n2/T;
f3=Fs2/n2*(0:n2-1);
subplot(212);plot(f3abs(y2));title(‘2倍插值心電信號的頻譜圖‘);xlabel(‘頻率/Hz‘);ylabel(‘|X2(k)|‘);axis([0360-1800]);grid?on;
?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????3024??2019-07-14?11:02??\mamayu1314-9409158-Unti
?????文件??????????36??2019-07-14?11:02??\no.txt
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