S-Parameters simulation in ADS

Hi all,
I was trying to find the s-parameters for a single regular transistor in ADS. I have connected the port terminal resistances in both at the gate and also at the drain. I have also attached the DC block capacitors, DC feed inductors and separate biasing votlage Vdc sources for both gate and also for the drain.

For some reasons,my simulation for s parameters always shows a single point in the centre of the smith chart no matter what the frequency range is.I am sure I am doing mistake somewhere.could anyone help me out in this.


falcon

What type of model you have used ? Have you ever checked the model itself ?
Post your simuation testbench here as a picture..then I can say something

firstly thanks for replying bigboss.
the schematic is attached below
if u need more details, lemme know

falcon

I guess the model parameters by default are not realistic.Change them with typical ones..

If this is an "IDEAL" Model and you are using Ideal Blocks & Chokes you
might just be seeing a Perfect match at all Freq's.
I assume you were looking at S11 or S22 On the Smith Chart.
Look at the gain S21 in db. See if it is a perfect Straight line over all Freq's.

You can also go on line and find a real transistor's S-Par file and use it in ADS.


Cheers