Darktrax
Full Member level 5
I get positive S11 when trying to simulate a trace with 2 vias. This is very confusing for
passive stuff. It's only about +0.28dB, but anything positive has got to be wrong!
This piece of trace is one of a pair intended to connect to the source tabs of a GaAsFET HEMT.
The simulator uses method-of-moments for planar EM simulation.
If anyone knows, or has seen this before, I could use a hint as to how to progress.
Is it the meshing? Something to do with frequency interpolations maybe?
![2vias-layout.jpeg 2vias-layout.jpeg](https://www.edaboard.com/data/attachments/28/28353-1de46c9d07a7425d701bfb41ad6b5198.jpg)
![2vias-S11.jpeg 2vias-S11.jpeg](https://www.edaboard.com/data/attachments/28/28354-8d6f0b4a74a9468d4446d20080caab18.jpg)
Thanks if you can help..
passive stuff. It's only about +0.28dB, but anything positive has got to be wrong!
This piece of trace is one of a pair intended to connect to the source tabs of a GaAsFET HEMT.
The simulator uses method-of-moments for planar EM simulation.
If anyone knows, or has seen this before, I could use a hint as to how to progress.
Is it the meshing? Something to do with frequency interpolations maybe?
![2vias-layout.jpeg 2vias-layout.jpeg](https://www.edaboard.com/data/attachments/28/28353-1de46c9d07a7425d701bfb41ad6b5198.jpg)
![2vias-S11.jpeg 2vias-S11.jpeg](https://www.edaboard.com/data/attachments/28/28354-8d6f0b4a74a9468d4446d20080caab18.jpg)
Thanks if you can help..