Synthesis equations for shielded suspended substrate microstrip line and broadside-coupled stripline

Simple and explicit equations for the synthesis of shielded suspended-substrate microstrip line (SSL) and broadside-coupled stripline (BSCL) are presented that are valid over a practical application range of structural parameters and dielectric constants of substrate in common use. Comparison of the results obtained using the developed synthesis equations with those obtained using the SUPERCOMPACT package (for SSL) and the finite-difference method (for BSCL) shows the accuracy to be within +or-3% and +or-3.5%, respectively, for the synthesis equations.<>