What is wrong with this 3 conductor coplanar wave guide model? I am using
the new modal port feature in ANSYS 10.0. Is my voltage and current path defined
correctly to obtain the characteristic impedance of the modal port?
If the outer conductors are not grounded you will have mixed
modes (3 modes possible.) This could cause poor results compared to
a benchmark solution. If there is no lossy material to absorb the higher modes,
the ports need to be internal ports with PML on the ends.
At 11.0 we will have an undocumented capability to output the characteristic
impedance and you will not have to make any paths. It is necessary to flag the end
of the central conductor with BF,ALL,CHARGE,1 with this method. In general, the current
path is created with as a closed loop around the center conductor