Is there FWHM function in frequency domain

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Hi all, i have a gaussian pulse in time domain, Can i find the fwhm in frequency domain of this pulse? In andvanced thanks

Accepted Answer

Star Strider
Star Strider on 10 May 2021
Try it —
a = 2;
p = @(t) exp(-(a*t).^2)
p = function_handle with value:
@(t)exp(-(a*t).^2)
t = linspace(-5,5);
figure
plot(t, p(t))
grid
P = fft(p(t))/numel(t);
Ts = t(2)-t(1);
Fs = 1/Ts;
Fn = Fs/2;
Fv2 = linspace(-Fn, Fn, numel(P));
figure
plot(Fv2, fftshift(abs(P)))
grid
xlabel('Frequency')
figure
findpeaks(fftshift(abs(P)), Fv2, 'Annotate','extents')
[pks,locs,w,p] = findpeaks(fftshift(abs(P)), Fv2, 'MinPeakProminence',0.01)
pks = 0.0877
locs = 0.0500
w = 1.0726
p = 0.0877
So, yes, using findpeaks.
  4 Comments
zahra
zahra on 6 Aug 2022
Hello, dear Star Strider
This part of the code written by you is as follows:
Fn = Fs/2;
Fv2 = linspace(-Fn, Fn, number(P));
I don't understand why it is fs/2? Please explain to me the reason.
Thank you
Star Strider
Star Strider on 6 Aug 2022
The Nyquist frequency, ‘Fn’, (the highest frequency that can be uniquely resolved in a sampled signal) is one-half the sampling frequency, ‘Fs’.

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