Coplanar Waveguide with Ground (Driven Terminal)

The coplanar waveguide (CPW) with ground plane is shown below.

Figure 1: Coplanar Waveguide with Ground

When using HFSS to model a transmission line it is not necessary to model the entire length explicitly. Instead create a short section and to generate the desired length for the model you only need to de-embed the appropriate distance from the wave port. For this model the explicitly solved length was chosen as a dimension typical of the cross-section such as spacing between conductors or a conductor thickness. This is done to keep the 3D mesh as close to a high quality as possible. So for a model of explicit length X and a desired simulation length Y one can de-embed from each port (Y-X)/2.

Figure 2: Ports with Deembedding

Deembedding greatly reduces the simulation effort.

Figure 3: Terminals

The resulting E field and vector fields are shown below.

Figure 4: E Field

Figure 5: Vector Field

The S-parameter plot is shown below.

Figure 6: S-parameter Plot