DrunkBear
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cpw 50ohm
Is there any principle, say the width and height, when setting the CPW port in CST.
i noticed the quite different calculated Line Impedance is obtained for ports with different width.
![](https://obrazki.elektroda.pl/98_1187257545_thumb.jpg)
![](https://obrazki.elektroda.pl/32_1187257810_thumb.jpg)
![](https://obrazki.elektroda.pl/55_1187257913_thumb.jpg)
![](https://obrazki.elektroda.pl/54_1187257972_thumb.jpg)
BTW, what does the following warning mean: "The degeneration of TEM modes at the homogeneous port 1 could lead to undetermined modepatterns. It might be suitable to define a multipin port instead" and what is its influence to the results?
Is there any principle, say the width and height, when setting the CPW port in CST.
i noticed the quite different calculated Line Impedance is obtained for ports with different width.
![](https://obrazki.elektroda.pl/98_1187257545_thumb.jpg)
![](https://obrazki.elektroda.pl/32_1187257810_thumb.jpg)
![](https://obrazki.elektroda.pl/55_1187257913_thumb.jpg)
![](https://obrazki.elektroda.pl/54_1187257972_thumb.jpg)
BTW, what does the following warning mean: "The degeneration of TEM modes at the homogeneous port 1 could lead to undetermined modepatterns. It might be suitable to define a multipin port instead" and what is its influence to the results?