A new tool for calculating the characteristic impedance of transmission lines using the FDE solver in MODE Solutions is available in the 2016b release. The transmission line examples including the stripline example have been updated to show the characteristic impedance tool.
A stripline is formed by a conducting strip in a substrate sandwiched by ground planes above and below the strip. The characteristic impedance of a mode supported by a stripline can be calculated using the built-in “Power and impedance integration” tool in MODE Solutions’ FDE solver. In this example, we consider a device with an inner strip of perfect electrical conductor with a finite thickness, as well as a 2D strip which can be more easily compared with analytic results where the strip is assumed to have zero thickness.