www.pudn.com > voiceprocessingtoolbox.rar > fftZeroPadding03.m

% This example demos the effect of zero-padding of DFT 
[y, fs]=wavread('welcome.wav'); 
signal=y(2047:2126);		% A full fundamental period 
len=length(signal); 
for i=1:3 
	x=[signal; zeros(len*(i-1), 1)]; 
	subplot(3,3,i*3-2); 
	plot(x, '.-'); 
%	title(sprintf('x[n] with N=%d',N)); 
	set(gca, 'xlim', [-inf inf]); 
 
	[mag, phase, freq]=fftOneSide(x); 
	subplot(3,3,i*3-1); 
	plot(freq, 20*log(mag), '.-'); 
	title('Magnitude of DFT of x[n]') 
	set(gca, 'xlim', [-inf inf]); 
 
	subplot(3,3,i*3); 
	plot(freq, phase, '.-'); 
	title('Phase of DFT of x[n]') 
	set(gca, 'xlim', [-inf inf]); 
end