CAD models for a boxed coplanar waveguide with multilayered substrates andoverlays

By the conformal mapping method, CAD-oriented analytical closed-form expres sions for the quasi-TEM parameters for a boxed coplanar waveguide (BCPW) wi th multilayered substrates and overlays are presented. The parameters inclu de the effective dielectric constant, the characteristic impedance, the wav elength of the guided wave, and the capacitance per unit length. All of the formulas obtained in this paper are simple and accurate enough for microwa ve circuits' designs and are useful for transmission line theory.