Using modulated data to define an amplitude curve

Use the modulated definition method to define the amplitude, a, as

a=A0+Asinω1(t-t0)sinω2(t-t0)     for t>t0,a=A0     for t≤t0,

where A0, A, t0, ω1, and ω2 are user-defined constants. For more information, see Defining Modulated Data.

  1. Display the Edit Amplitude dialog box as described in Selecting an amplitude type to define.
  2. Click the arrow to the right of the Time span field, and specify how you want to define the amplitude as a function of time:

    • Select Step time for time that is measured from the beginning of each step.

    • Select Total time for total time accumulated over all non-perturbation analysis steps.

  3. In the Initial amplitude field, enter A0.
  4. In the Amplitude field, enter A.
  5. In the Starting time field, enter t0.
  6. In the Circular frequency 1 field, enter ω1.
  7. In the Circular frequency 2 field, enter ω2.
  8. Click OK to save your amplitude definition and to close the Edit Amplitude dialog box.