Frequency Analysis by Simulink

Hi,

Can someone explain me the steps to do spectral analysis of a signal that I have in a .mat file (sample rate used=1kHz).

I would like to display signal in frequency domain and extract some parameters as mean frequency.

I've tried to use spectrum scope block but it returns an error in some S-function.

Thanks

[Fangjun Jiang]

What is the error message?

Answer 1

[Rick Rosson]

I would recommend trying it in MATLAB first. In the following code, I am assuming that the signal is stored in an M x 1 array called x, and that the sampling rate is a scalar called Fs:

   filename = ...
   x = load(filename);

   Fs = 1000;
   M = size(x,1);
   dF = Fs/M;
   f = -Fs/2:dF:Fs/2-dF;

   X = fftshift(fft(x));

   figure;
   plot(f,abs(X));

HTH.

Rick

[cyberdyne]

Ok. But I would like to make it by Simulink blocks (using .mat file block), how could I do it ?

Answer 2

[Rick Rosson]

Alternaitively, you could use the function freqz. For more information:

   >> doc freqz

HTH.

Rick