The greeN data represents the real data from a GP2 car, the blue is the simulated data.
I got the idea to use the pwelch from the MoTeC website.
http://www.motec.com/forum/viewtopic.php?f=26&t=85
From MATLAB site,
Pwelch is a spectrum estimator. It computes an averaged squared
magnitude of the Fourier
transform of a signal. In short, it computes a set of smaller FFTs
(using sliding windows),
computes the magnitude square of each, and averages them.
Also, note the display default for Pwelch is in dB (logarithmic).
