www.pudn.com > voiceprocessingtoolbox.rar > firstOrderFIR.m

alpha=linspace(-0.99, 0.99, 13); 
N=100; 
 
h=freqz([1 -0.95], 1, N); 
 
h=[]; 
for i=1:length(alpha), 
	fr=freqz([1 alpha(i)], 1, 100); 
	db=10*log10(fr.*conj(fr)); 
	h = [h, db]; 
end 
plot(linspace(0, 0.5, N), h); 
title('Frequency response of H(z)=1+\alphaz^{-1}'); 
ylabel('Decibel'); 
xlabel('Normalized Freq'); 
 
legendStr={}; 
for i=1:length(alpha), 
	legendStr={legendStr{:}, ['\alpha=', num2str(alpha(i))]}; 
end 
legend(legendStr);