[SOLVED] Some questions about Momentum..

simulating in mw mode site:edaboard.com

I'm on a project that works at 1.9GHz what will be consisted of passive circuits on a silicon substrate.

I have some question in my mind about " differential ports"

These are compiled as single ports but when this the case , source impedance will be what ? I mean if they are recognized as a single port How I can simulate this "Data Set of Momentum" in a schematic simulation page? Because there are 11 ports and in Momentum simulation every single port is terminated by 50Ohm and in reality, these ports won't be terminated 50 Ohm , maybe some different terminations..

Second question..

How can we choose MW mode and RF Mode ? In fact in Reference Guide of Momentum the difference between them is not VERY clear..And obviously , the results seem to be different. But the worst is measurment is a little bit far away from simulation results.

In that case which simulation mode will be used in which case??

Is there anybody who has great exprience on ADS Momentum ? I'm gonna be appreciate..

You can terminate each single port to 100 Ohms or even better use an ideal transformer (lots of them in the included components of ADS).
Avoid using RF mode in momentum for it only provides a rough indication for the result (but it is much faster).

Always keep in mind when simulating passive structures on semiconductive substrate:
(i) for inductors the metalization layer for RFIC is quite thick compared to the substrate - read the very nice application notes of Agilent on the subject.
(ii)2.5D simulators like momentum do not provide very accurate results
for simulations with "thick" metals, try using a full 3d simulation package for cross checking

Glad if I was any help

I compared results from Momentum's Microwave mode with results from CST for planar structures. And I had very good agreement between theirs.

In Momentum (the Layout window) you can define each port real and imaginary. You go to "Momentum"-->"Port Editor..." and type in your value.
HP has a great tech support, if you get stuck they will help.
Hope this helps