Example: Define a Sine Wave Pulse

Define a sine wave pulse with a delay of 0.3 ns and a duration of 0.5 ns.

Define Step(t) = 1 for t > 0.3 ns

On the Create time signal dialog, in the f(t) field, add the following to define a step function with a delay of 0.3 ns:

f ( t ) = s t e p ( t − 300 e − 12 )

Figure 1. The Signal preview shows the step function with a delay of 0.3 ns.


Define a Rectangular Pulse

In the f(t) field, define a rectangular pulse with a duration of 0.5 ns by extending Equation 1 to:

f ( t ) = s t e p ( t − 300 e − 12 ) − s t e p ( t − 800 e − 12 )

Figure 2. The Signal preview shows the rectangular pulse with a delay of 0.3 ns with a duration of 0.5 ns.


Define a Sine Wave Pulse

  • In the f(t) field, define a sine wave pulse with a delay of 0.3 ns and a duration of 0.5 ns by extending Equation 2 to:
    f ( t ) = ( s t e p ( t − 300 e − 12 ) − s t e p ( t − 800 e − 12 ) ) * sin ( 2 * 3.14 * ( t ) * 7 e 9 )
    Note: Predefined variables are not supported. Use a value of 3.14 instead of pi.
    Figure 3. The Signal preview shows the sine wave pulse with a delay of 0.3 ns and a duration of 0.5 ns.


    Note: Equation 3 and Figure 3 correspond to a modulated step signal at 7e9 GHz.
  • Add a delay of 0.3 ns to the sine wave by extending Equation 3 to:
    f ( t ) = ( s t e p ( t − 300 e − 12 ) − s t e p ( t − 800 e − 12 ) ) ∗ sin ( 2 * 3.14 * ( t - 300 e - 12 ) * 7 e 9 )
    Figure 4. The Signal preview shows the final sine wave pulse.