Frequency domain and windowing

Hello there,

I want my frequency domaine to be windowed by a 8192 and 4096 window. But unlike the examples online I don't generate my signal. It was recorded and afterwards transoformed into the frequency domaine.

So how do I write the code for the windowing with an already existing signal?

Answer 1

[Star Strider]

It depends on the information you have. If you have the complex Fourier transform or the amplitude and phase information, it would be possible to invert it and then do the windowed Fourier transform. If all you have is the amplitude information, then (unfortunately) all hope to invert it is lost.

[Leo Dokoza]

I am sorry but I do not understand.

I sent ultra sonic waves to different surfaces and recorded the reflected signals. My sensor works with 16 384 samples. After the measurement I already did a FFT and my Professor liked the results. Now he wants to see a window with 8192 or 4096 samples.

[Star Strider]

Since you already have the time-domain data, just use that. I thought all you had was the Fourier transform of your data, and my Answer described how to recover the time-domain data from it.

To do a windowed Fourier transform, see if the stft function will do what you want.