How to extract phase and amplitude information from FFT?
85 views (last 30 days)
Show older comments
I am doing signal processing of radar data. I applied butturworth bandpass filter and applied fft to the radar data.I want to know how to extract the phase and amplitude information of radar data so i can add it to my ideal radar simualation and make it non ideal :D . Thanks
load('fb2040'); % loading the data
x = fb2040(3,:);
y_filt = filter(b,a,x); % filtering the received signal
nfft = length(y_filt);
res = fft(y_filt,nfft)/ nfft; % normalizing the fft
f = fs/2*linspace(0,1,nfft/2+1); % choosing correct frequency axes
res = res(1:nfft/2+1);
figure, plot(f,abs(res));
xlabel('Frequency in MHz');ylabel('Amplitude');
return
0 Comments
Accepted Answer
Adam
on 26 Jun 2015
If you want the phase and amplitude for different frequencies then these are just:
angle( res );
real( res );
or
abs( res );
if you want the magnitude rather than amplitude.
2 Comments
Peter Mbamaluikem
on 13 Jul 2017
Hi, Adam what if there are several frequencies and one is to extract the magnitude of one say 60Hz. what will the code be?
Adam
on 14 Jul 2017
'res' in the above code is a vector of results corresponding to the frequencies in 'f' in the original code in the question so just find the 'f' that is closest to 60Hz and take the magnitude of that value rather than the whole vector.
More Answers (0)
See Also
Categories
Find more on Spectral Measurements in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!