Inverse Fourier Transform ignores oscillations

1 Ansicht (letzte 30 Tage)
Steven
Steven am 18 Okt. 2019
Bearbeitet: Steven am 22 Okt. 2019
Hi. I am doing some time and freq analysis. So lets say I have some x-t data, I use fft to take them in freq domain, do some calculations and finally do ifft to return them back into the time domain. But after getting the ifft, I get the red plot, while the blue plot is obtained from another source (which appranely should be true).
I am not sure which one is correct? How come the ifft is ignoring the oscilaltions?
Thanks in advance.
  8 Kommentare
Walter Roberson
Walter Roberson am 20 Okt. 2019
fftshift() to convert fft representations.
Bjorn Gustavsson
Bjorn Gustavsson am 20 Okt. 2019
Based on your question and comments it is clear (this will come off as a bit abrasive) that you should read up on what you do when Fourier-transforming data and what happens with the Fourier-transform when you do operations on it (what multiplication in the Fourier-domain corresponds to in the time-domain etc).

Melden Sie sich an, um zu kommentieren.

Antworten (0)

Kategorien

Mehr zu Fourier Analysis and Filtering finden Sie in Help Center und File Exchange

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by