FFT

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Fast Fourier Transform-
In this experiment, we learned to write the c program to perform FFT of  4 point and 8 point signals. We had learned about FFT algorithm in class before coming for practical. So we had basic idea about FFT flowgraphs in theory DFT operation is faster but in practical FFT algorithm is faster.
Generally Radix-2 length signals are preferred in FFT algorithm, but we can reduce any no. of length of signal into prime no. base FFTs. For longer sequences, FFT takes more time for output computation as the no. of stages in the Flowgraph increase.  

Comments

  1. UnknownMay 15, 2018 at 7:13 AM

    FFT is suitable for practical apllications, Also long length signals can be broken into into prime factor radices.

    ReplyDelete
    Replies
    1. UnknownMay 15, 2018 at 10:17 PM

      But for long data sequences output computation takes longer time so we prefer OAM and OSM.

      Delete
  2. utkarsha@tilakMay 15, 2018 at 7:13 AM

    FFT produces fast results than DFT

    ReplyDelete
    Replies
    1. UnknownMay 15, 2018 at 10:17 PM

      The parallel computations in FFT makes it faster than DFT.

      Delete
  3. MayurLankhande2510May 15, 2018 at 7:37 AM

    The fast operation of FFT algorithm is well explained as the number of computations are lesser than DFT.

    ReplyDelete
  4. tilakmunshiMay 15, 2018 at 9:12 AM

    FFT gives an advantage of parallel processing.

    ReplyDelete
    Replies
    1. UnknownMay 15, 2018 at 7:48 PM

      But if we input signal is of longer length the stages in FFT flowgraph increases making the output signal delayed.

      Delete
  5. Omkar SawantMay 15, 2018 at 10:00 AM

    FFT can be done only on Radix 2 input signal so for non Radix 2 signal we have to first convert it in radix 2 form

    ReplyDelete
    Replies
    1. UnknownMay 15, 2018 at 7:46 PM

      Yes, for non radix 2 no.s we first decompose that number in prime factors and then perform FFT algorithm.

      Delete

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