I am playing with the
periodogram of MATLAB. I created a simple script to observe how it behaves:
rng(1); %# initialize the random number generator Fs = 1000; %# Sampling frequency duration = 0.1; %# seconds A = 1; %# Sinusoid amplitude f = 150; %# Sinusoid frequency eps = 0.01; t = 0:1/Fs:duration; x = A * sin(2*pi*f*t) + eps * randn(size(t)); periodogram(x,,1024,Fs);
I have no problem with the code and can write my own
periodogram function using the algorithms given in the documentation but I wonder the theoretical reason behind the comb-like hills which are not 150 Hz. What do I get those instead of getting a single spike over 150 Hz? Is there anything special in the distances of the peaks of these hills?