Plot on Smith Chart from HB Simulation

Dear All,

To design an outphasing combiner, I need to extract the input impedances when the circuit is driven by two sources concurrently with a varying phase-shift and plot them on a Smith Chart. However, I can't find a way to display the simulated S-parameters on a Smith Chart.

The testbench, shown below, consists of two sources set to 50 Ohm with variable phase (PORT0: theta, PORT1: -theta) swept from -90° to 90°. The NPORTs are couplers used to isolate the forward and reflected power at each source, i.e. the S-parameters are:

• S13 = S31 = 1; through path
• S21 = S41 = 1; forward and reflected power
• All other are zero

The testbench is simulated with an "hb" analysis instead of "sp", as the two sources have to be excited simultaneously with varying phase-shift to see their load-modulation effect. The sweep is setup in the "Choosing Analysis" window. The powers of the forward (pXa) and reflected (pXb) waves are found through the "Direct Plot" window, e.g. pvr('hb "/p1a" 0 50.0 '(1)) as the power for p1a, and named P1A_Watt. The S-parameters are then calculated as the reflected power w.r.t. the forward power P1B_Watt/P1A_Watt. This approach is based on a Hot S-parameter testbench from ADS.

At this point I would like to display these S-parameters on a Smith Chart. However, this seemed more challenging than expected. One straightforward method would seem to create an empty Smith Chart window in the Display Window and dragging the S-parameters from the rectangular plot on it, but this just deletes them from the Display Window. Hence my question:

How can I display these S-parameters on a Smith Chart?