CAD models of dispersion and losses for multilayer coplanar waveguide

We present the closed-form models of conductor thickness dependent dispersive line parameters and losses, of multilayer CPW on isotropic dielectric substrates. The partial capacitance technique has been used for conformal mapping of the multilayered CPW structure. The dispersive empirical expressions for the single-layer CPW from literature are improved to include the finite conductivity and finite conductor thickness in propagation characteristics and losses. The single layer reduction formulation of lossy multilayer CPW is then used to extend the closed-form models developed for computation of line parameters, to multilayer structures. All developed models are verified against the results obtained using the EM-simulators for frequency range 1 GHz - 60 GHz over wide range of parameters. The average deviation of the model against the comparison is 3.5 %.