i've got two questions about the matlab periodogram function:
How can I recover the amplitudes from the periodogram?
fs=100;
fn=fs/2;
L=2^12;
df=fs/L;
t=0:1/fs:(L-1)/fs;
x=1*sin(2*pi*(df*floor(10/df))*t)+2*sin(2*pi*(df*floor(20/df))*t)+3*sin(2*pi*(df*floor(30/df))*t);
periodogram(x,[],L,fs);