www.pudn.com > cyclostationary_toolbox.rar > ex5.m, change:2007-10-17,size:452b

clear; 
clc; 
%A=1;B=1; 
fb=7;fa=100;fs=600;N=1024; 
t=0:1/fs:1024/fs; 
x=cos(2*pi*fa*t+cos(2*pi*fb*t)); 
figure(1) 
plot(t,x); 
axis([0 1 -1 1]); 
xlabel('\fontsize{9}\fontname{标楷体}时间/s');ylabel('\fontsize{9}\fontname{标楷体}幅值/um'); 
x1=x.*x; 
y=fft(x1,N); 
Pyy=sqrt(y.*conj(y))/N; 
figure(2) 
ff=fs*(0:N/2)/N; 
plot(ff(1:N/2+1),Pyy(1:N/2+1)); 
xlabel('\fontsize{9}\fontname{标楷体}循环频率/Hz');ylabel('\fontsize{9}{R_{x}}^{\alpha}(0) /um^2')