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Representing graphically an analog signal?

  1. Jul 16, 2006 #1
    I was wondering,how do I represent graphically an analog signal components in time and frequency using an equation for example like this:

    v(t)=3 + 1.414cos(w0t) - 1.414sin (w0t) + 2cos(2w0t + 5pi/2)

    Thanks in advance for the reply!
  2. jcsd
  3. Jul 16, 2006 #2

    Andrew Mason

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    Calculate v(t) for different values of t. Plot the values for v(t) on the vertical axis for values of t on the horizontal axis.

  4. Jul 17, 2006 #3
    But in the equation,what are the values that correspond to the amplitude and frequency?
  5. Jul 17, 2006 #4
    It may be more enlightening to use the variable x = w0*t. x varies from 0 to 2*pi; one needn't know what w0 is. The angular frequency of the equation you wrote is w0; amplitude I'm not sure about. If you have to plot it anyway, might as well do that and find the maximum deviation from 3 (the DC value).
  6. Jul 17, 2006 #5

    Claude Bile

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    Plotting the frequency domain is simple - just plot the Fourier transform. Because the frequency components are discrete, you will get a series of delta functions of varying heights (depending on the amplitude of each component).

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