[SOLVED] ADS resistance calculation

[Lathas]

When I connect a microstrip line with impedance of 31ohm at 0Hz(trying to take the value of impedance for DC calculation), to a resistance of 50ohm, I am getting a resistance of 48.5ohm. The microstrip portion is realized as component in momentum layout and resistor from the lumped component pallete during ADS simulation. What is happening here?

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Shouldn't I be getting 81ohms?

 

[tyassin]

Hello,

If we are talking about 0 Hz, then you should measure only your lumped resistor of 50 ohm. The microstrip line is just a piece of copper(with extremely little resistance).
At much higher frequencies it becomes a impedance question. Here it will be from a transmissionline point of view...depending on the length of line, frequency etc.

Regards

 

[Lathas]

The problem was that the component must be characterized for 0Hz during the cosimulation. After adding the 0Hz point in the layout model generation, it showed correct results (negligible real part) for the microstrip and combined resistance of 50ohms.