How to Interpret FFT results ??

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Add
Add on 1 Aug 2016
Commented: Star Strider on 1 Aug 2016
My code for fft looks like this :
R_mags = abs(fft(dtec));
N = length(dtec);
fs = 0.0333333333 ; % samples per second
fax_bins = (1 : N-1);
fax_Hz = fax_bins*fs/N;
N_2 = ceil(N/2);
plot((1./fax_Hz(1:N_2))/60 , R_mags(1:N_2))
xlabel('Period(mins)')
ylabel('Magnitude');
title('Gravity Wave Signatures in F-region TEC: Station-Port Blair','fontsize', 14, 'fontweight', 'bold');
axis tight
And the result plot looks like the jpg file attached here.
What do I interpret in terms of the frequency and Time period of the waves seen in the image. Someone help. Thanks

Answers (1)

Star Strider
Star Strider on 1 Aug 2016
It is difficult for me to follow your code. I would implement the function using this version of the fft documentation.
  2 Comments
Add
Add on 1 Aug 2016
I have followed from code given in this link :
https://dadorran.wordpress.com/2014/02/20/plotting-frequency-spectrum-using-matlab/#5
Star Strider
Star Strider on 1 Aug 2016
I would use the code in the link I provided.

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