shiyan1.m

有关信号波形、幅值谱、相位谱

clear all;
t=0.001:0.001:0.512;
A=10*sin(60*pi*t+pi/4)+5*sin(120*pi*t+pi/3);
B=12*cos(60*pi*t+pi/2)+4*sin(120*pi*t+pi/6);
x=fft(A,512);
y=fft(B,512);
f=1000/512*(0:127);

figure(1)
p=y.*conj(y)/512;
plot(f,p(1:128))

xlabel('Hz');
ylabel('Y轴');
figure(2)
s1=abs(x)*2/512

s2=abs(y)*2/512;
plot(f,s2(1:128))

figure(3)
g1=angle(x);
g2=angle(y);
plot(f,g2(1:128));
 
figure(4)
Mlag=512


rx1=xcorr(A,Mlag,'biased');


subplot(211);


plot(A(1:Mlag));


xlabel('n');


ylabel('x1(n)');grid on;


subplot(212);


plot((-Mlag:Mlag),rx1);grid on;


xlabel('m');ylabel('rx1(m)');

figure(5)%互相关
Rxy=xcorr(A,B);
Rxx0=sum(A.*A);
Ryy0=sum(B.*B);
rm=Rxy/sqrt(Rxx0*Ryy0);
plot((-Mlag+1:Mlag-1),rm);
grid;
figure(6)%互相干
cohere(A,B);


fn=5;% fn表示分解的层数
TT=wpdec(x2,fn,'db40','shannon')%小波包分解
plot(TT);