how to extend time after fft ?
15 vues (au cours des 30 derniers jours)
Afficher commentaires plus anciens
omar thamer
le 8 Nov 2013
Commenté : omar thamer
le 13 Nov 2013
I have a signal runs for 500 seconds ( 1:1:500 sec) after i did the fft, i want to go back to time domain and see how the signal looks like for 1000 Seconds (1:1:1000) ? Any advice how to extend the time ? Is it better to do it in frequency domain ? Is it simply to add the sines and cosines with loops ?
Thank you
0 commentaires
Réponse acceptée
Vilnis Liepins
le 11 Nov 2013
You can try edft.m on fileexchange http://www.mathworks.com/matlabcentral/fileexchange/11020-extended-dft
ifft(edft(YourData,1500),1500)
Signal for 1000 sec will be ifft output 1:1000.
2 commentaires
Plus de réponses (1)
Walter Roberson
le 8 Nov 2013
Try
ifft(fft(YourData), 1000)
2 commentaires
Walter Roberson
le 11 Nov 2013
fft() assumes that its data is periodic, so to get 1000 seconds of output, ifft() to get the 500 second output and then replicate it.
Voir également
Catégories
En savoir plus sur Fourier Analysis and Filtering dans Help Center et File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!