UdaraDe Silva

RF vendors often provide S-parameter files (Touchstone format) for their components. These files can be used in ADS simulations to decide which component to use in your RF design. This tutorial explains how to import the touchstone file from the vendor website and generate the S-parameter plots.

Step 1: Download the S-parameter file

We will simulate the splitter from here which is MMIC power splitter operating in 1.7-3 GHz range.

Step 2: Import file to ADS

Open a new schematic in ADS and add N-Port S-Parameter file block from Data items. Use the browse option to select the downloaded touchstone file in the block properties.

Step 3: Add S-parameter simulation

Select the Simulation-S_parameters blocks and add SP block and 3 termG blocks. Connect the three “termG” blocks to the 3 ports of the splitter using wires. Change the start, stop and step frequencies to the operating frequency range of the device and then run the simulation.

Step 4: Add the measurments

The simulation results need to be shown in a rectangular plot which can be done as follows.

Summary

This simple example shows how to generate S-parameter plots from vendor-provided touchstones files in ADS. We used a 3-port power splitter in this example but the same method applies to N-port devices.