Performing an S-Parameter Simulation

Start by creating your design, then add current probes and identify the nodes from which you want to collect data.

For a successful analysis, be sure to:

• Apply ports to all inputs and outputs. Use P_1Tone or P_nTone power sources to drive inputs. Terminate all other ports using port-impedance terminations (Term). Verify impedance. The Term component is found on the Simulation-S_Param palette. Power sources are on the Sources-Freq Domain palette.
• Check the Num field for each port. The S-parameter port numbers are derived from these fields. For a 2-port circuit, you would want the input labeled as Num=1 and the output as Num=2.
• Add the S-parameter component to the schematic and double-click to edit it. For a basic simulation, fill in the fields under the Frequency tab:
  • Select the Sweep type, single point, logarithmic, or linear. For a linear or logarithmic sweep, elect to define the sweep with start/stop or center/span values.
• To calculate admittance or impedance parameters, enable the options under the Parameters tab.
• Group delay calculations can be enabled from the Parameters tab.
• You can enable frequency conversion, which is useful when analyzing circuits with standard (not user-defined) behavioral mixer models. This option is under the Parameters tab.
• To calculate noise, select the Noise tab and enable Calculate noise . You select a node for noise calculations from the Edit list, then click Add. Use the Mode list to sort the noise contributed by individual noise sources by name or value.

For details about each field, click Help from the dialog box.

For more detailed descriptions of simulation setups, refer to Examples of S-Parameter Simulation.