Complex Circuit Input Impedance Software

[Wavelengthman]

Looking for software that will calculate the input impedance of a 2 terminal passive complex circuit made of several components R L C and any type and combination of transmission lines.

 

[logbook]

Any SPICE software with scripting capability should be able to do this. I use SIMetrix. If you drive the circuit with constant current then plot the voltage you effectively get the impedance.

 

[Wavelengthman]

Thanks for input. It appears that it does not include balanced RF tranmission lines and seems to indicate that it only handles series losses for now. Is there a program that permits multiple lines connected in any manner to arrive at a desired result. i.e. take several balanced transmission lines - connect any # of the lines inputs say in parallel across an input pair of terminals - connect the line outputs to various elements R L or C or another line? Looking for a software simulator that permits the selection of several elements R L C (R L C elements connected in any manner - parallel/series etc.) & including balanced transmission lines of any length interconnected in any combination and calculate the input impedance over the desired frequency range. I would assume it would be able to show the RF currents / voltages / phase at each node at any frequency if desired. I sure appreciate your help & others that have had to calculate similar circuits. Thanks

 

[leonar40]

I am assuming that you just haved a design, not an actual proto-type of the circuit correct? If you had a real one, then you could just hook it up to a network analyzer and get the loss between your two ports.

 

[Wavelengthman]

Thanks leonar40 - well I have a prototype but do not have a network analyzer (wish I did!) The nature of the circuit needs a software program to give me results of ruff manual calculations (manual calculations with a cptr sitting here is a no no ) Hope that someone finds software that really only needs to handle passive loss and lossy elements only - R L C and balanced transmission lines...... surely someone has developed these -- looking at mainly the input Z characteristics and V / I / phase characteristics at various nodes.
Thanks all for your inputs......

 

[dpc]

You might look at this:

http://www.arrl.org/catalog/9043/tlw.pdf

I'm not sure if it is general enough for your application, but it might be a starting point.