Magnitude & Phase output for FFT Function with Windowing

Debdatta_Sen

Hi all,

I have a time domain curve which I would like to convert into frequency domain.

By doing so I would like to obtain the magnitude and phase output from the curve. 
I need the Windowing function as well. Something like what fft hanning does in HyperGraph.
Is there a similar function in Compose?
The output I need should have both Magnitude and Phase components, something like this:

<?xml version="1.0" encoding="UTF-8"?>
 

L Moretti

Hello Debdatta,

 

you can use the user defined function (attached to this reply) with this syntax:

 

[AmpFFT,PhFFT,f] = FFTeval(s,Fs);

 

s: your signal values

Fs: sampling frequency

AmpFFT: apmlitude of the single sided spectrum

PhFFT: Phase of the single sided spectrum

f: frquency vector

 

you can then plot your results:

 

figure()

plot(f,AmpFFT)

figure()

plot(f,PhFFT)

 

Of course you can also apply windows to your signal. There are many built windows ready to be used.

Your script will be:

 

w = hann(numel(s),'periodic');  %window

s = s .* w;  % windowing 

[AmpFFT,PhFFT,f] = FFTeval(s,Fs);

 

Other windows you can use:  hamming, kaiser, blackman... (just look inside the SignalProcessing library)

 

Hope it helps,

 

Lorenzo

 

 

Unable to find an attachment - read this blog

manoj kandukuri

Hi Debdatta, 

You can use 'real' & 'angle' commands to get magnitude and phase of fft signal

 

real(ft)
angle(ft)

 

thanks,

Manoj kandukuri