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Time-domain to frequency domain

  1. Jul 7, 2012 #1
    How will the graph of a sine wave (plotted against time axis) of a particular frequency look like if the same is plotted against frequency???
  2. jcsd
  3. Jul 7, 2012 #2


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    Single sine wave frequency domain graph is a delta function at the frequency of the sine wave.
  4. Jul 7, 2012 #3
    Do you mean that there will be single thin line rising upto 1 corresponding to that frequency only?
  5. Jul 7, 2012 #4


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    from a practical point of view, for an example of this your could compare 2 different pieces if test equip used for measuring/displaying a signal
    An Oscilloscope gives a time domain view ... the y ( vertical ) axis is amplitude
    the x axis is time .... you will see the signal ( frequency ) displayed as a series of cycles on the screen

    A Spectrum Analyser gives a frequency domain view .... again you have y axis as amplitude, but in the x axis is frequency, there is only that single vertical line representing that frequency

  6. Jul 9, 2012 #5
    There is a second delta function at the negative frequency. In addition, there's a phase shift of \pi/2.
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