Software for simulating microwave systems?

[f95toli]

I have been trying to find a free (or cheap) software package that can be used to simulate microwave systems (i.e. NOT an EM simulation package) but so far I haven't had much luck.
Essentially I would like to be able to "build" systems with mixers, circulators, amplifiers, waveguides etc and then be able to plot parameters like S11 and S21. It would be great if it could also handle time-domain data (e.g. pulse propagation). It would also be a plus if it can import s2p data.

I know there are commercial software packages that can do this, e.g. Microwave Office and the RF Toolbox for Matlab but they are VERY expensive so -at least at the moment- they are not really an option.

Any suggestions?

 

[Corneo]

I think what you are asking is quite a lot of computing power. I don't know of any free/cheap software that can handle all that. Agilent's ADS can do exactly what your asking for. But it isn't cheap at all.

 

[Ulysees]

For what it's worth, many PhD students and researchers were experimenting with the "transmission line matrix" method in the mid-90s, someone must have come up with a commercial product out of it. Maybe even freeware. I would try something like 'TLM freeware' in google.

 

[f95toli]

I think what you are asking is quite a lot of computing power. I don't know of any free/cheap software that can handle all that. Agilent's ADS can do exactly what your asking for. But it isn't cheap at all.

I don't think it is THAT complicated. ADS is as far as I remember a full EM solver which I don't need. What I am looking for is more akin to SPICE but for microwave components; software where is possible to build systems by combining (mainly cascading) 2- or 3-port models of components. This is obviously not as accurate as a "real" solver, but should be good enough for what I want to do.

The weird thing is that there seem to be quite a few free EM modellers (I use Sonnet Lite from time to time) out there; but nothing for systems despite the fact that the latter should be much simpler.