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Finding Frequency Components with a FFT in Excel

  1. Aug 14, 2010 #1
    So I'm doing some signal processing and I want to take a signal and find the frequency components and so I need to do the discrete fourier transform. The problem is I'm not sure how about to go about finding them. I'm using excel at the moment just because I vaguely know how to use it.

    Anyway as an example I thought I'd try and find the frequency components of a sine wave, there should only be 1 and it should be 1/2pi.

    Here is a screenshot of the excel sheet.


    What I've done is created a sine wave, taken the FFT using the data analysis add-on, then taken the modulus using the "IMABS" function and plotted it as a line graph. You can see an appropriate spike though the numbers are meaningless. I imagine you see two spikes because of the periodic nature of the fourier transform. What do I have to do next to find the frequency?

    Edit: Forgot to mention I would be incredibly grateful if anyone can help me!
    Last edited: Aug 14, 2010
  2. jcsd
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