jasonkee111
Junior Member level 3

Hi. I can't find a place to discuss on theory. So, i decide to post it here. Hope that anyone can answer for query..
FYI, i read the Understand Digital Signal Processing.pdf
Background:
From the book, When sampling a continuos time-domain function, having a CFT, and take the DFT of those samples, the DFT results in a frequency domain sampled approximation of CFT.
Question
Why can we use the output of CFT to perform the DFT?
Reason to ask:The output of continuous fourier transform(CFT) is in frequency domain ( continuos signal ) while the input of DFT (before tranformation) have to be in discrete.
Thanks a lot
FYI, i read the Understand Digital Signal Processing.pdf
Background:
From the book, When sampling a continuos time-domain function, having a CFT, and take the DFT of those samples, the DFT results in a frequency domain sampled approximation of CFT.
Question
Why can we use the output of CFT to perform the DFT?
Reason to ask:The output of continuous fourier transform(CFT) is in frequency domain ( continuos signal ) while the input of DFT (before tranformation) have to be in discrete.
Thanks a lot