www.pudn.com > estimate-ar.rar > p508.m

%program p508 
%Black_turkey 
m=1:255; 
k=-500:500; 
w=(pi/500)*k; 
R=k/500; 
 
r0=0.9141; 
r2=r(257:511) 
X=r2*cos(pi/500*m'*k)+r0; 
magX=abs(X); 
subplot(211); 
plot(R,magX); 
xlabel('Angular frequency,ω (π)'); 
ylabel('Pbt(ω)'); 
title('Black_Turkey功率谱曲线') 
 
%AR 
HH=zeros(1,1001); 
w=(pi/1000)*k; 
a1=-0.195  
a2=0.95;  
var=1; 
 
H=1+a1*exp(-j*pi/500*k)+a2*exp(-j*2*pi/500*k); 
magH=abs(H); 
 
i=1 
while i<1001 
   HH(i)=1/magH(i).^2; 
   magH(i)=magH(i+1);      
   i=i+1 
end 
HH(1)=1/magH(1).^2; 
HH(1001)=1/magH(1001).^2; 
subplot(212) 
plot(R,var*HH) 
xlabel('Angular frequency,ω (π)'); 
ylabel('Par(ω)'); 
title('AR功率谱曲线')