Buenos

The component (connectors, chips) vendors provide their models with 2k-8k samples. I have no way of resampling them before inserting htem into QUCS. So the software has to support existing model files we obtain on the market.

The component vendors provide their models with 2k-8k samples. I have no way of resampling them before inserting htem into QUCS. So the software has to support existing model files we obtain on the market.

If I try to import anything larger than maybe 60MBytes S-parameter file, the simulator crashes with an error. For professional simulations in digital electronics, we need to chain together multiple S-par files that are 32 ports each, having maybe 4000 samples, that is more than 500MBytes. If we insert 4 Spar files, each being 600MBytes, that is 2.4GBytes. Typical error message: line 500880: memory exhausted checker error, found 6 options checker error, option s' occurred 2x checker error, options'...

Hello. Normally we would run TDR si sims on S-parameter models. That would require a convolution-based transient solver, that QUCS does not have. I tried to run an S-par sim, then use formulas to produce a TDR plot, but I think I have some bugs in my calculations. If you can make formulas correctly, including FFT, then you might be able to do TDR in QUCS, in S-par sim model, not in transient sim. This is my template that includes TDR computation from Spar: https://www.buenos.extra.hu/download/Ch...

Hello. Normally we would run TDR si sims on S-parameter models. That would require a convolution-based transient solver, that QUCS does not have. I tried to run an S-par sim, then use formulas to produce a TDR plot, but I think I have some bugs in my calculations. If you can make formulas correctly, including FFT, then you might be able to do TDR in QUCS, in S-par sim model, not in transient sim.

"see the thread above." Above where? I have the same problem, cannot simulate with 36port Spar models.

I have noticed that the FEXT crosstalk seems to be proportional to the rise time in the simulation results. If we look at a FEXT s-parameter curve in another simulator, we can notice that FEXT linearly increases with the knee frequency (f=0.35/trise), but only up to fmax=0.5/t_pd. bove that it goes up and down periodically, and lingers around -60...-20dB. On a 5" trace that limit is 0.5GHz. TNT MMTL still gives me linearly increasing FEXT as I keep changing the rise time parameter in the range of...

This doesnt work, even though the documentation lists it as an existing feature: M[:,3] Vector consisting of 3rd column of matrix M checker error, no appropriate function for `M[range('?','?'),3]' found