- 2nd July 2007, 12:16 #1

- Join Date
- Feb 2006
- Posts
- 102
- Helped
- 3 / 3
- Points
- 1,994
- Level
- 10

## advantages of dft

Hi all, i want to know if dtft can be calculated using dft what are its advantages.One can calculate the dtft directly.why to use dft.

Any response in this regard would be helpful.

regards

wajahat.

- 2nd July 2007, 12:16

- 3rd July 2007, 19:25 #2

- Join Date
- Jun 2007
- Posts
- 26
- Helped
- 4 / 4
- Points
- 1,087
- Level
- 7

## advantages of dft over dtft

Hi,

DFT is completely discrete both in frequency and time, however DTFT is only discrete in time but continueous in frequency. DTFT is not used in actual digital signal processing, its DFT which is mostly calculated using fast algorithms called FFT algorithms.

- 3rd July 2007, 19:25

- 6th July 2007, 18:01 #3

- Join Date
- Feb 2006
- Posts
- 102
- Helped
- 3 / 3
- Points
- 1,994
- Level
- 10

## advantages of dft method

jahmad quoted

DFT is completely discrete both in frequency and time, however DTFT is only discrete in time but continueous in frequency. DTFT is not used in actual digital signal processing, its DFT which is mostly calculated using fast algorithms called FFT algorithms.

Any explanation of the above queries would be helpful.

Thanks

wajahat

- 6th July 2007, 18:01

- 13th July 2007, 03:58 #4

- Join Date
- Aug 2004
- Posts
- 226
- Helped
- 47 / 47
- Points
- 2,928
- Level
- 12

## calculating the dtft from the dft

Your second question (comprehensively answered by jahmad ) is completely different from the first question. Hope thats your intention.

Obviously, you cannot deal with infinite sequnces in pratice, you always do the FT on a limited number of samples.

-b

- 20th July 2007, 16:00 #5

- Join Date
- Mar 2006
- Location
- My Love Iran
- Posts
- 231
- Helped
- 41 / 41
- Points
- 3,315
- Level
- 13

## advantages fft over dft

Hi

Signal processing of infinite (or finite and long duration) signals is done with truncation of signal with some known window. You can search this method by searching window.