The model which is created from linesim contains two differential ports (1,-1) and (2,-2). As a result you get a differential mode s parameter with two ports. In post process this is used to calculate a single ended 4 port model. This process has some limitations compared to setting up geometries inside mgrid including full access to various port types.
The linesim solution with integrated access to the 3D solver solution is intended to expand the accurately covered bandwidth of the linsim via models in the range of 10Gbps+. No additional license is needed for this but it has limitations. For full access to all modelling capabilities like port wizard and others a separate 3D solver license is required.
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